In line with Census Office’s revisions and corrections policy, thorough quality checks will take place on all census statistics which are released. Census Office may occasionally need to revise statistics and update information.
Details of where Census Office have discovered an issue with or correction to Census 2021 data are contained in the log for easy reference.
DI002: Accommodation type
Type: Issue
Date added: 15 December 2022
Comment
Household question 7 on the 2021 Census questionnaire asks ‘What type of accommodation is this?’ with tick box options given for recording a response.
Census Office has noted differences in classification declared by a small number of respondents for accommodation type when compared to the accommodation type recorded by Land and Property Services (LPS) for the address. This can be explained by census respondents favouring selecting ‘semi-detached’ instead of ‘terraced (including end-terrace)’ for end-terrace properties.
It is consistent with previously published Office for National Statistics (ONS) research comparing responses to the 2011 Census question ‘What type of accommodation is this?’ with data trained surveyors have reported to the Valuation Office Agency (VOA). The ONS research identified a preference for 2011 Census respondents to define their property as ‘semi-detached’ instead of ‘end-terrace’ in approx. 3% of cases.
This issue is related to the classification selected by respondents and does not affect the total number of properties recorded.
DI001: Rounding difference between census data published in May 2022 and September 2022
Type: Issue
Date added: 22 September 2022
Comment
The main statistics demography tables that form part of the ‘Census 2021 main statistics for Northern Ireland (phase 1)’ release supersede the population and household estimates published in the 24 May 2022 release, which reported statistics solely at the Northern Ireland level.
In May 2022, NISRA published rounded Northern Ireland level population and household estimates. At that time, the dataset was still being subjected to a number of final statistical procedures; these statistical procedures have been applied to the census database, and the unrounded statistics are now available. A number of figures at the Northern Ireland level (when rounded to the nearest 100) differ from the May figures as detailed in Table 1 and 2.
| Category | May 2022 rounded figure | Finalised rounded figure |
|---|---|---|
| Usual residents | 1,903,100 | 1,903,200 |
| Usual residents: 30-34 years |
126,000 | 126,100 |
| Usual residents: 55-59 years |
129,200 | 129,300 |
| Usual residents: 60-64 years |
113,000 | 113,100 |
| Females: 30-34 years |
64,800 | 64,900 |
| Females: 40-44 years |
62,900 | 63,000 |
| Females: 50-54 years |
67,000 | 66,900 |
| Males | 936,200 | 936,100 |
| Males: 40-44 years |
59,300 | 59,200 |
| Males: 60-64 years |
55,400 | 55,300 |
| Category | May 2022 rounded figure | Finalised rounded figure |
|---|---|---|
| Households | 768,900 | 768,800 |