485. The CES Recommendations for the 2020 census round, as well as those for the 2010 round, noted that in many countries the pattern of family and household formation is changing, and so it is important to examine the structural changes that are occurring.

486. The significant changes in living arrangements and the emergence of new household types reported in many countries in the UNECE region seen in the previous decade have continued since the 2010 round. Trends have included, for instance, a later start of family life, increased cohabitation, same-sex marriages and partnerships, larger numbers of one person households and lone-parent families as a result of divorce, more reconstituted families, and increased proportions of people living in more than one household.

487. Many phenomena can be examined equally from the perspective of the private household, the family nucleus, or the individual. For instance, statistics related to one-parent families could be examined from the perspective of the household (e.g., number of households composed of a one-parent family), the family (e.g., number of one-parent families), or the person (e.g., number of persons/children/parents in one-parent families).

488. In considering topics related to households it is important that countries are aware of the different concepts relating to households and families. Some of the key issues were specifically investigated in the UNECE survey, and this chapter reviews the practices in the 2020 census round regarding the adoption of a number of these concepts, definitions and classifications associated with the structure and characteristics of households (both private and institutional) and families.

489. The CES Recommendations offers two different concepts for defining private households. The so-called housekeeping concept defines (in paragraph 768) a household as being “…. either a one-person household, that is a person who lives alone in a separate housing unit or who occupies, as a lodger, a separate room (or rooms) of a housing unit but does not join with any of the other occupants of the housing unit to form part of a multi-person household as defined below; or a multi-person household, that is a group of two or more persons who combine to occupy the whole or part of a housing unit and to provide themselves with food and possibly other essentials for living. Members of the group may pool their incomes to a greater or lesser extent.”.

490. Some countries may be unable to collect data on households based on this housekeeping concept, for example where their census is register-based. Many such countries use a different concept – the household-dwelling concept – which considers all persons living in the same housing unit to be members of the same household, such that there is one household per occupied housing unit and the number of occupied housing units and the number of households occupying them are equal (para. 770).

491. In the CES Recommendations, institutional households are defined as “comprising persons whose need for shelter and subsistence are being provided by an institution” (para. 772), where an institution is understood to be a legal body for the purpose of long-term inhabitation and provision of services to a group of persons.

492. The UNECE survey included questions on the concepts of private and institutional households used by countries in the 2020 round. The main results are summarized in Table 90. For private households, the housekeeping concept was used by 43% of the countries (20 out of 46), while in the 2010 round it was used by 70% of the countries. The household-dwelling concept was used by almost all countries with register-based census (only Belgium and Slovenia used the housekeeping concept) and by almost half of the countries with field enumeration or combined census. Of the countries that used the household-dwelling concept, only four (Finland, Hungary, Luxembourg and Slovenia) are able to estimate the number of private households according to the housekeeping concept.

493. Concerning institutional households, almost all countries (93%) reported compliance with the CES Recommendations definition and only three countries reported non-compliance: Armenia, where institutional households are not included in the sample used in combination with registers; Finland, where the institutional population is included in the census, but institutional households cannot be formed; and the United States, where the different concept “group quarters” is used, that reflects better user needs, and is consistent with other surveys and previous censuses.

	Total (out of 46 countries)	Type of census
		Field enumeration (16 countries)	Combined (17 countries)	Register-based (13 countries)
Private household concept used
Housekeeping concept	20	9	9	2
Household-dwelling concept, of which…	26	7	8	11
Can estimate the number of private households according to the housekeeping concept	4	0	3	1
Institutional household
Definition used fully comply with CES recommended definition	39	13	16	10
Definition used does not fully comply with CES recommended definition	3	1	1	1

494. There are some persons who do not usually live in either private or institutional households. These are often referred to as the ”homeless”. The CESR noted (para. 779) that ”homelessness” is essentially a cultural definition based on concepts such as ”adequate housing”, ”minimum community housing standard” or ”security of tenure”, which can be implemented in different ways by different communities. For certain policy purposes, some persons living in institutions may be considered as ”homeless” persons, as can people who frequently stay temporarily with different households, without secure access to anyone. As such, ”homelessness” is not a clearly defined characteristic for the purposes of international comparisons.

495. For tabulations, the CESR distinguished two categories of homelessness (para. 780):

(a) Primary homeless (or roofless): This category includes persons living in the streets without a shelter that would fall within the scope of living quarters.

(b) Secondary homeless (or houseless): This category includes persons with no place of usual residence who make use of various types of accommodations (including dwellings, shelters, institutions for the homeless or other living quarters) and have a roof over their heads at the census reference time. This category includes persons living in conventional dwellings but who report having no usual address on their census form. Such people are to be regarded as usually resident at the address at which they are enumerated and as part of the household at that address.

496. The UNECE survey asked countries whether they used in their census the concepts of primary and secondary homelessness and, if so, whether the definitions used were compliant with those included in the CESR. The results are presented in Table 91.

497. The concept of primary homelessness was used by 22 of the 39 reporting countries (56%), including three quarters of those with a field enumeration census and less than one third of those with a register-based census. Of the 22 countries that used the concept, 18 adopted a definition fully compliant with the CESR, and 4 a definition partially compliant.

	Total (out of 39 countries)	Type of census
		Field enumeration (13 countries)	Combined (13 countries)	Register-based (13 countries)
Primary homelessness – concept used	22	10	8	4
Definition fully compliant with CESR	18	9	6	3
Definition partially compliant with CESR	4	1	2	1
Concept not used	17	3	5	9
Secondary homelessness – concept used	14	5	7	2
Definition fully compliant with CESR	9	5	3	1
Definition partially compliant with CESR	5	0	4	1
Concept not used	23	7	5	11

498. The concept of secondary homeless was used by only 14 countries (36%), including only two countries with a register-based censes. Moreover, only 9 countries used a definition fully compliant with the CESR, and 5 countries used a definition only partially compliant. In Germany, persons are counted as secondary homeless only when they are registered in a shelter home. Various countries (Czechia, Italy and Luxembourg) specified that they are not able to distinguish between primary and secondary homelessness.

499. In the CESR, a child is defined as a blood, step-, or adopted son or daughter (regardless of age or marital status) who has usual residence in the household of at least one of the parents, and who has no partner or own child(ren) living in the same household. Grandsons and granddaughters of at least one grandparent who have usual residence in the household but where there are no parents present may also be included. Foster children should not be included (para. 785).

500. Based on the UNECE survey, 38 countries out of 43 (88%) used a definition of child that fully complies with the CES recommended definition, including all 13 countries with a register-based census (see Table 92). In France, only persons who are legally single can be considered as children. In the Russian Federation, persons under 18 years of age who are married and/or have children are not considered as children.

501. The CES Recommendations also stated that a child who alternates between two households (for instance after his or her parents have divorced or separated) should be considered to be a member of the household (and hence the family within that household) where he or she spends the majority of the time. Where an equal amount of time is spent with both parents, the child should be considered to be a member of the household/family where he/she is present at the census reference time (para. 785).

502. About 30% of the reporting countries (11 out of 43) did not fully comply with the CES Recommendations on the allocation of children who alternate between two households, including almost half of the countries with a register-based census.

	Total (out of 43 countries)	Type of census
		Field enumeration (14 countries)	Combined (16 countries)	Register-based (13 countries)
Definition of child
Definition used fully complies with CESR definition	38	11	14	13
Definition used does not fully comply with CESR definition	5	3	2	0
Allocation of children who alternate between households
Allocation applied fully complies with CES Recommendations	30	12	11	7
Allocation applied does not fully comply with CES Recommendations	13	2	5	6

503. In various countries using registers (including Belgium, Iceland, Latvia, Luxembourg, Norway, Switzerland and Türkiye) the registered place of residence is considered. In the United States the location of children who alternate households is reported by respondents, however the idea of “usual residence” is employed, so that the child should be reported in the household where they spend the most time.

504. In the CES Recommendations, the term couple refers to married couples, registered couples, and couples who live in a consensual union (whether of the opposite or same sex). Two persons are considered to be partners in a consensual union when: they have usual residence in the same household, they are not married to, nor are in a registered/legal partnership with, each other, and they have a marriage-like relationship with each other (para. 786).

505. Of the 43 reporting countries, 37 (86%) used a definition of couple fully compliant with the CES Recommendations (Table 93). In the 2010 round, only 67% of the countries did so.

	Total (out of 43 countries)	Type of census
		Field enumeration (14 countries)	Combined (16 countries)	Register-based (13 countries)
Definition of couple
Definition used fully complies with CESR definition	37	13	14	10
Definition used does not fully comply with CESR definition	6	1	2	3

506. Based on the categories of relationships to the reference person reported by countries (Table 99), the same-sex spouse or registered partner relationship can be identified in 16 countries, including 5 with a field enumeration census, 6 with a combined census and 5 with a register-based census. There is a high overlap between countries that can identify same-sex partners and at the same time same-sex spouse or registered partner. Up to 14 of them can identify both relationships. One country (Bulgaria) can only identify same-sex partners, and two countries (Finland and Portugal) can only identify same-sex spouse or registered partner.

507. The same-sex partners relationship can be identified in 15 countries, including 5 with a field enumeration, 6 with a combined census, and 4 with a register-based census.

508. Based on the categories of relationship to other household members used as part of the household matrix approach (Table 100 below), the same-sex registered partners relationship can be identified in 10 countries, including 3 with a field enumeration census, 4 with a combined census and 3 with a register-based census. There is a high overlap between countries that can identify same-sex partners and at the same time same-sex registered partner. Up to 10 of them can identify both relationships. In Slovakia and Spain can only identify same-sex partner relationships. In Slovakia, there is no legal regulation allowing registered partnerships.

509. The same-sex partner relationship can be identified in 12 countries. Of the 12 countries that could identify same-sex partner relationships, 3 did a field enumeration census, 5 a combined census and 4 a register-based census.

510. In the CES Recommendations (paras. 783-784), a family nucleus is defined in the narrow sense as two or more persons who live in the same household and who are related as marital, registered, or consensual union (that is, cohabiting) partners of either opposite or same sex, or as parent and child. Thus, a family comprises a couple without children, or a couple with one or more children, or a lone parent with one or more children.

511. The family concept as defined above limits relationships between children and adults to direct (first-degree) relationships, that is, between parents and children. In some countries, numbers of ”skip-generation households”, that is, households consisting of grandparent(s) and one or more grandchild(ren) but where no inter-generational parent (that is the parent of those grandchildren) is present, are considerable. Therefore, countries may include such skip-generation households in their family definition.

512. All countries used a definition that fully complies with the CES Recommendations, but only 10 countries used a definition that includes both first-degree relationships and skip generation households (Table 94). In the United States – which was the only country that used a definition not fully compliant with the CES Recommendations – the family includes all household members related to the household reference person by birth, marriage or adoption. Cohabiting partners are not considered to be related to each other.

	Total (out of 45 countries)	Type of census
		Field enumeration (16 countries)	Combined (16 countries)	Register-based (13 countries)
Definition of family
Definition used fully complies with CESR definition, of which…	44	15	16	13
including first-degree relationships only	34	11	11	12
including both first-degree and 'skip generation' households	10	4	5	1
Definition used does not fully comply with CESR definition	1	1	0	0

513. In the CES Recommendations, a three-generation household is defined (para. 787) as consisting of two or more separate family nuclei or one family nucleus and (an)other family member(s), containing at least three generations. The youngest two generations should always constitute one family nucleus. For example, a woman who is living in a household with her own child(ren) and her own parent(s) should be regarded as being in the same family nucleus as the child(ren) even if she has never been married. Her own parents would then constitute a second family nucleus within the same household.

514. Over two thirds of the reporting countries (28 out of 40) reported that data on three-generation household can be produced from census data and in all those countries but one the definition used complies fully with the recommended definition (Table 95). In the United Kingdom multi-generational households are defined as households where people from across more than two generations of the same family live together. However, the definition recommended by the CES could be derived.

515. A three-generation household can be constructed by all countries with a combined type of census, and almost all those with a traditional census, but less than half of those with a register-based census.

	Total (out of 41 countries)	Type of census
		Field enumeration (14 countries)	Combined (14 countries)	Register-based (12 countries)
Data on three-generation households can be produced…	29	10	14	5
and the definition used fully complies with CESR definition	28	9	14	5
but the definition used does not fully comply with CESR definition	1	1	0	0
Data on three-generation households cannot be produced	12	5	0	7

516. The term reconstituted family in the CESR (para. 788) refers to a family consisting of a married, registered or cohabiting couple, with one or more children, where at least one child is the natural child of only one member of the couple. If the one partner subsequently adopts the natural child of the other partner, the resulting family ceases to be a reconstituted family.

517. Table 96 presents the results of the UNECE survey on the number of countries that produced data on reconstituted families and which methods were used (multiple replies were possible). Exactly half of the responding countries produced data on reconstituted families, but only 4 of the 11 countries with a register-based census. All countries that produced data on reconstituted families used a definition that fully complies with the CESR. The method used by most countries (12) to produce the data is the relationship to the reference person, while 9 countries used the household relationship matrix.

	Total (out of 40 countries)	Type of census
		Field enumeration (15 countries)	Combined (14 countries)	Register-based (11 countries)
Data on reconstituted families can be produced (and the definition used fully complies with CESR definition), using…	20	8	8	4
Relationship to the reference person of the household	12	6	4	2
Household relationship matrix	9	5	2	2
Partial household relationship matrix	1	0	1	0
Other method	3	1	0	2
Data on reconstituted families cannot be produced	20	7	6	7

518. In the CESR, an extended family is defined (para. 791) as a group of persons who live together in the same household, including one or more family nuclei and other persons who do not constitute a family nucleus as defined above but are related to each other or to any members of any family nuclei in the same household (to a specified degree) through blood, marriage or adoption.

519. In the 2020 census round, 28 countries out of 40 (70%) produced data on extended families, all but two of them using a definition that fully complies with the one recommended by the CES (Table 97).

	Total (out of 40 countries)	Type of census
		Field enumeration (15 countries)	Combined (14 countries)	Register-based (11 countries)
Data on extended families can be produced…	28	11	11	6
and the definition used fully complies with CESR definition	26	9	11	6
but the definition used does not fully comply with CESR definition	2	2	0	0
Data on extended families cannot be produced	12	4	3	5

520. The household and family status of persons within private households is primarily based on the information collected on the core topic of relationship between household members. The 2020 CESR noted (in paragraph 793) that in previous censuses, the selection of the one reference person in the household to whom all other household members report or designate their relationship was the recommended method for mapping household structures. When the household's reference person is chosen carefully, this method gives accurate information for most household and family types. In certain cases, however, such as in multiple family households, this method will not always give the information that is required. Therefore, a more elaborative method – the household relationship matrix approach – has been developed for the collection of the relationships between all household members. The CESR noted that information collected via the matrix method may be only practicable for those adopting a traditional, questionnaire-based census, and that information obtained from registers is unlikely to identify all such intra-household relationships.

521. The UNECE survey showed that that the reference person approach was adopted by 20 countries (47%), the relationship matrix by 15 countries (35%), and 8 countries used other approaches (Table 98). In the 2010 round, the reference person approach was more dominant, adopted by 33 countries (65%).

522. While the CESR stated that the relationship matrix method may be only practicable for countries adopting a traditional, questionnaire-based census, several countries that used registers reported having adopted this method, or a “partial matrix” approach based on the information available in the registers.

523. The UNECE survey included some additional questions related to this topic. One of them inquired on how the household reference person was identified. The results are also presented in Table 98 (multiple replies were possible). Among the criteria proposed in the question, 10 countries selected the identification of the reference person based on age and family relationships, chosen to facilitate the family determination. This criterion corresponds to what was recommended in the CESR (para. 800). Other criteria selected by most countries include the free choice of the reference person by the respondents among the adults living in the household (12 countries), and the household member considered as being the household head by all the other members (9 countries).

524. The UNECE survey also asked countries that did not use the household relationship matrix approach about the reasons for not using it (Table 98). The reasons selected by most (seven) countries are that the household matrix method necessitated substantial modifications to the data processing and dissemination processes, and that the use of a population register makes it difficult to collect such information.

	Total (out of 43 countries)	Type of census
		Field enumeration (15 countries)	Combined (15 countries)	Register-based (13 countries)
Approach used
Reference person approach	20	9	8	3
Relationship matrix approach	15	5	5	5
Another approach	8	1	2	5
How was the household reference person identified? (multiple replies possible)
It was freely chosen by respondents, among the adults living in the household	12	4	8	0
It was identified according to criteria such as age and family relationships, chosen to facilitate the family determination	10	3	3	4
It was the member considered as being the household head by all the other members	9	7	2	0
It was the one resulting from the population register or other administrative register	5	0	2	3
It was the member who contributed the most income	2	1	0	1
Other	11	4	2	5
What was/were the main reason(s) for not using the household relationship matrix approach? (multiple replies possible)
The household matrix method necessitated substantial modifications to the data processing and dissemination processes	7	4	1	2
The use of a population register makes it difficult to collect such information	7	0	3	4
The household matrix concept was not consistent with other statistical surveys	4	3	1	0
The household matrix method did not work well with respondents during testing (for reasons of complexity, clarity, confidentiality or other)	2	0	2	0
Other	9	2	3	4

525. The CESR recommended a classification of persons living in a private household by relationship only to the household's reference person (para. 802), in order to facilitate the identification of family nuclei and households. The classification was recommended at the one-digit level and optional at the two-digit level.

526. The UNECE survey inquired on the compliance of countries with the categories of that classification. The results are presented in Table 99. The most common categories are the closest family relationships: (2.0) reference person’s spouse or registered partner (reported by 27 out of 31 countries); (4.0) child of reference person and/or of husband/wife/partner (27 countries); (6.0) father or mother of reference person, of spouse, or of cohabiting partner of reference person (26 countries)

	Total (out of 31 countries)	Type of census
		Field enumeration (13 countries)	Combined (12 countries)	Register-based (6 countries)
Categories
(1.0) Reference person	31	13	12	6
(2.0) Reference person’s spouse or registered partner	27	10	12	5
(2.1) Opposite sex spouse or registered partner	19	6	8	5
(2.2) Same-sex spouse or registered partner	16	5	6	5
(3.0) Reference person’s partner in consensual union (cohabiting partner)	22	6	11	5
(3.1) Opposite-sex partner	19	6	8	5
(3.2) Same-sex partner	15	5	6	4
(4.0) Child of reference person and/or of husband/wife/ partner	27	11	11	5
(4.1) Child of reference person only	18	7	8	3
(4.2) Child of reference person's husband/wife/ partner	14	5	7	2
(4.3) Child of both	13	6	5	2
(5.0) Husband/wife or cohabiting partner of child of reference person	22	8	10	4
(6.0) Father or mother of reference person, of spouse, or of cohabiting partner of reference person	26	10	12	4
(7.0) Other relative of reference person, of spouse, or of cohabiting partner of reference person	24	10	11	3
(8.0) Non-relative of reference person of the household	24	10	11	3
(8.1) Foster child	6	3	3	0
(8.2) Boarder	5	3	2	0
(8.3) Other (including live-in domestic employee)	11	4	5	2
Other categories	14	7	4	3

527. With reference to the household relationship matrix, the CESR recommended a classification of persons living in a private household by relationship to other household members (para. 796). The classification was recommended at the one-digit level and optional at the two-digit level.

528. Table 100 presents the compliance of countries with the categories of that classification, as reported in the UNECE survey. As expected, also in this case the most common categories are the closest family relationships: (1.0) other person's husband/wife/spouse (reported by 21 countries); (3.0) other person's partner in consensual union (18 countries); (4.0) other person's child (18 countries); (5.0) other person's father or mother (19 countries); (6.0) other person's other relative  (17 countries).

	Total (out of 31 countries)	Type of census
		Field enumeration (8 countries)	Combined (8 countries)	Register-based (5 countries)
Approach used
(1.0) Other person's husband/wife/spouse	21	8	8	5
(1.1) Opposite sex partner	14	4	5	5
(1.2) Same-sex partner	12	3	5	4
(2.0) Other person's registered partner	12	3	5	4
(2.1) Opposite sex registered partner	10	3	3	4
(2.2) Same-sex registered partner	10	3	4	3
(3.0) Other person's partner in consensual union (cohabiting partner)	18	5	8	5
(3.1) Opposite-sex cohabiting partner	15	4	6	5
(3.2) Same-sex cohabiting partner	12	4	5	3
(4.0) Other person's child	18	6	7	5
(5.0) Other person's father or mother	19	7	7	5
(6.0) Other person's other relative	17	8	5	4
(7.0) Non-relative of other person	14	7	5	2
(7.1) Foster child	2	1	0	1
(7.2) Boarder	1	1	0	0
(7.3) Other (including, for example, live-in domestic employee)	4	2	2	0
Other categories	6	4	0	2

529. The CES recommended that information should be derived for all persons on their status or position in the household and, for people in private households, whether they are living alone, in a nuclear family household or living with others (CESR para. 808). The classification was recommended at the three-digit level (paras. 809-810)

530. Table 101 presents information on how many countries derived information on household status, and how many considered the categories of the classification. Information on household status was produced by 41 of the 43 reporting countries (95%). All the sub-categories of (1.1) persons in a nuclear family household were considered by most countries (three quarters or more). Some sub-categories of persons in other private households with relatives and/or non-relatives (1.2.2,1.2.3,1.2.4), and primary homeless persons (2.2) were problematic – particularly for countries with a register-based census – and were considered by only about half of the countries.

	Total (out of 43 countries)	Type of census
		Field enumeration (16 countries)	Combined (14 countries)	Register-based (13 countries)
Information on household status derived	41	16	13	12
(1.0) Person in a private household	40	14	14	12
(1.1) Person in a nuclear family household	37	12	13	12
(1.1.1) Husband/male spouse or registered partner	36	12	14	10
(1.1.2) Wife/female spouse or registered partner	35	11	14	10
(1.1.3) Male partner in a consensual union	31	9	13	9
(1.1.4) Female partner in a consensual union	31	9	13	9
(1.1.5) Lone father	35	11	14	10
(1.1.6) Lone mother	35	11	14	10
(1.1.7) Child under 25 years of age	32	8	14	10
(1.1.8) Son/daughter aged 25 or older	31	8	13	10
(1.1.9) Other persons not member of the nuclear family, but in a nuclear family household	35	11	14	10
(1.2) Person in other private households	31	9	12	10
(1.2.1) Living alone	36	11	13	12
(1.2.2) Living with relatives	22	9	9	4
(1.2.3) Living with non-relatives	23	10	9	4
(1.2.4) Living with relatives and non-relatives	25	10	10	5
(2.0) Person not in a private household	34	11	12	11
(2.1) Person in institutional household	34	11	13	10
(2.2) Primary homeless person	23	8	10	5
(2.3) Other	14	7	3	4
Information on household status not derived	2	0	1	1

531. As was the case for household status, the CESR similarly recommended (in paragraph 813) that information should also be derived for all persons on their family status in terms of being either a partner, a lone parent, or a child. The classification was recommended at the two-digit level and optional at the third digit level.

532. As showed in Table 102, 40 of the 43 responding countries (93%) derived information for person on their family status. All the categories at the first two digit levels were considered by most countries (three quarters or more). For the categories at the third digit, many countries, particularly those with a register-based census, could not identify a child who was related to only one parent in a couple.

	Total (out of 43 countries)	Type of census
		Field enumeration (15 countries)	Combined (15 countries)	Register-based (13 countries)
Information on family status derived	40	13	15	12
(1.0) Partner	34	9	13	12
(1.1) Husband in a married couple / registered union	36	10	15	11
(1.2) Wife in a married couple / registered union	35	10	15	10
(1.3) Male partner in a consensual union	32	9	14	9
(1.4) Female partner in a consensual union	32	9	14	9
(2.0) Lone parent	35	9	14	12
(2.1) Lone father	34	9	15	10
(2.2) Lone mother	34	9	15	10
(3.0) Child	39	12	15	12
(3.1) Child aged under 25	34	9	15	10
(3.1.1) Child of both partners	21	6	11	4
(3.1.2) Child of male partner only	18	4	10	4
(3.1.3) Child of female partner only	18	4	10	4
(3.1.4) Child of lone father	31	7	15	9
(3.1.5) Child of lone mother	30	7	15	8
(3.2.) Son/daughter aged 25 or over	33	8	15	10
(3.2.1) Son/daughter of both partners	22	8	12	2
(3.2.2) Son/daughter of male partner only	17	5	10	2
(3.2.3) Son/daughter of female partner only	17	5	10	2
(3.2.4) Son/daughter of lone father	30	7	15	8
(3.2.5) Son/daughter of lone mother	30	7	15	8
Information on family status not derived	3	2	0	1

533. Taking into account the definition of family nucleus (see para. ‎510 above) the CES recommended classifying family nuclei by type (CESR para. 822-823).

534. Information on the type of family nucleus was derived by the large majority of countries (40 out of 43, that is the 93%), including all countries with a register-based census (Table 103).

535. Only one third of the countries identified reconstituted families (5.0). This category was considered optional by the CESR (para. 824), and an abbreviated version of the classification was suggested for countries that did not wish to distinguish reconstituted families. All the other categories were identified by most countries.

	Total (out of 43 countries)	Type of census
		Field enumeration (15 countries)	Combined (15 countries)	Register-based (13 countries)
Information on type of family nucleus derived	40	13	14	13
(1.0) Husband-wife family, not reconstituted family	31	8	12	11
(1.1) Without resident children	33	8	14	11
(1.2) With at least one resident child under 25	30	6	13	11
(1.3) Youngest resident son/daughter 25 or older	28	5	12	11
(2.0) Cohabiting couple, not reconstituted family	28	6	12	10
(2.1) Without resident children	30	7	13	10
(2.2) With at least one resident child under 25	27	5	12	10
(2.3) Youngest resident son/daughter 25 or older	27	5	12	10
(3.0) Lone father	36	10	14	12
(3.1) With at least one resident child under 25	31	6	13	12
(3.2) Youngest resident son/daughter 25 or older	30	6	12	12
(4.0) Lone mother	36	10	14	12
(4.1) With at least one resident child under 25	31	6	13	12
(4.2) Youngest resident son/daughter 25 or older	29	6	11	12
(5.0) Reconstituted family	13	4	7	2
(5.1) With at least one resident child under 25	14	2	10	2
(5.2) Youngest resident son/daughter 25 or older	13	2	9	2
Information not derived	3	2	1	0

536. The CES recommended countries to collect information on different types of private households, using a three-digit classification (CESR para. 835-836).

537. Information on the type of family nucleus was derived by all countries but one (Table 104). Most countries (three quarters or more) were able to identify the categories at the first two digits. About 40% of countries had difficulty in making the distinction at the third level, between households with or without other (non-family) members.

	Total (out of 42 countries)	Type of census
		Field enumeration (14 countries)	Combined (15 countries)	Register-based (13 countries)
Information on type of private household derived	41	14	14	13
(1.0) Non-family households	40	13	14	13
(1.1) One-person households	40	13	14	13
(1.2) Multi-person households	40	13	14	13
(2.0) One-family households	37	12	12	13
(2.1) Husband-wife couples without resident children	37	12	14	11
(2.1.1) Without other persons	24	7	9	8
(2.1.2) With other persons	24	7	10	7
(2.2) Husband-wife couples with at least one resident child under 25	33	8	14	11
(2.2.1) Without other persons	22	5	9	8
(2.2.2) With other persons	22	5	10	7
(2.3) Husband-wife couples, youngest resident son/daughter 25 or older	30	6	13	11
(2.3.1) Without other persons	22	5	9	8
(2.3.2) With other persons	21	5	9	7
(2.4) Cohabiting couples without resident children	30	8	13	9
(2.4.1) Without other persons	22	6	9	7
(2.4.2) With other persons	22	6	9	7
(2.5) Cohabiting couples with at least one resident child under 25	29	7	13	9
(2.5.1) Without other persons	21	5	9	7
(2.5.2) With other persons	21	5	9	7
(2.6) Cohabiting couples, youngest resident son/daughter 25 or older	29	7	13	9
(2.6.1) Without other persons	21	5	9	7
(2.6.2) With other persons	21	5	9	7
(2.7) Lone fathers with at least one resident child under 25	35	8	14	13
(2.7.1) Without other persons	24	6	10	8
(2.7.2) With other persons	23	6	10	7
(2.8) Lone fathers, youngest resident son/daughter 25 or older	33	7	13	13
(2.8.1) Without other persons	22	5	9	8
(2.8.2) With other persons	21	5	9	7
(2.9) Lone mothers with at least one resident child under 25	35	8	14	13
(2.9.1) Without other persons	24	6	10	8
(2.9.2) With other persons	23	6	10	7
(2.10) Lone mothers, youngest resident son/daughter 25 or older	33	7	13	13
(2.10.1) Without other persons	22	5	9	8
(2.10.2) With other persons	21	5	9	7
(3.0) Two or more-family households	32	8	13	11
Information not derived	1	0	1	0

538. The CESR defined the tenure status as the arrangement under which a private household occupies all or part of a housing unit (para. 847), and provided a classification that was recommended at the one digit level and optional at the two-digit level (para. 848).

539. Most countries (38 out if 42, that is 90%) collected or produced information on tenure status (Table 105). The optional distinction between categories (2.1) and (2.2) was produced by a limited number of countries.

	Total (out of 42 countries)	Type of census
		Field enumeration (15 countries)	Combined (14 countries)	Register-based (12 countries)
Information on tenure status of households collected – categories used:	38	14	12	12
(1.0) Households of which a member is the owner of the housing unit	37	13	12	12
(2.0) Households of which a member is a tenant of all or part of the housing unit	33	12	11	10
(2.1) Households of which a member is a main tenant of all or part of the housing unit	10	5	3	2
(2.2) Households of which a member is a sub-tenant of an owner occupier or main tenant	4	2	2	0
(3.0) Households occupying all or part of a housing unit under other form of tenure	23	9	8	6
Information not collected	4	1	2	1

540. The UNECE survey also inquired whether countries included in their censuses various non-core topics on families and households that were described in the CES Recommendations (Table 106).

541. The non-core topics that were included in the census by most countries are single or shared occupancy (12 countries), telephone and internet connection (11 countries, plus two countries that collected internet connection only), rent and other housing costs (9 countries), number of cars available for the use of the households (9 countries).

542. In general, countries with a register-based census are not able to produce most of those topics.

Topics	Total (out of 31 countries)	Type of census
		Field enumeration (15 countries)	Combined (11 countries)	Register-based (5 countries)
Single or shared occupancy	12	8	4	0
Telephone and Internet connection	11	7	3	1
Rent and other housing costs	9	5	4	0
Number of cars available for the use of the household	9	5	2	2
Availability of car parking	7	4	2	1
Durable consumer goods possessed by the household	2	2	0	0