Civometry calculation
Sentenced prisoners per 100,000 residents by ethnicity
Sentenced prison population of England and Wales at the end of the quarter (MoJ offender management Table 1.Q.7), per 100,000 usual residents in the same ethnic group (ONS Census 2021, TS021 broad groups).
How it is calculated
- Numerator
- Sentenced prison population by ethnicity · split by ethnicity
- Denominator
- Census 2021 ethnic group (five broad groups) · split by Ethnic group
- Formula
- numerator ÷ denominator × 100,000
- Result is measured in
- per 100,000 residents
- Which population is used
- latest census on or before numerator period (Census 2021)
- Suppressed when
- the numerator is below 10 or the population below 1,000, so small numbers are not published as rates
How the categories are matched
The two sources do not use the same category names. Every numerator category is mapped to exactly one denominator category, and nothing is merged or dropped silently.
| In the numerator | Matched to |
|---|---|
| Asian or Asian British | Asian, Asian British or Asian Welsh |
| Black or Black British | Black, Black British, Black Welsh, Caribbean or African |
| Mixed | Mixed or Multiple ethnic groups |
| White | White |
| Other ethnic group | Other ethnic group |
Not matched: Not stated, Not recorded. These records have no population to divide by, so no rate is calculated for them. They are shown as counts rather than hidden.
What it covers
England and Wales prisons, sentenced prisoners only (remand and non-criminal prisoners are excluded by the numerator); month-end snapshots from June 2025.
What this calculation cannot tell you
- The numerator is a stock (people in prison on one day) and includes foreign nationals, who are in the census denominator only if they were usual residents on census day.
- Prison ethnicity is as recorded on the prison system; "Not stated" and "Not recorded" are shown as their own rows.
- The denominator is the resident population on 21 March 2021 for every snapshot.
- Crude rates only; prisoners are concentrated in the 18–40 age range and the age structure differs between groups, so the crude rate is not an age-adjusted comparison.
Check it yourself
Every calculated value stores the numerator, the denominator and the identifiers of the two official observations it came from. Open the numerator and denominator above, take the figures for the same period and category, and apply the formula. If you get a different answer, tell us where it diverges.