To ask the Secretary of State for Justice, what proportion of all determinate custodial sentences handed down to (a) men and (b) women were served in prison.

Data on releases from prison is published regularly in the Offender Management Statistics:

https://www.gov.uk/government/statistics/offender-management-statistics-quarterly-october-to-december-2018

Tables A3.2i and ii of Prison Releases 2018 show that the mean average proportion of the sentence served in prison by males released from determinate sentences in 2018 was 65%, the median proportion was 55%. For females the mean average was 50% and the median was 45%. This data includes both standard determinate sentences, for which the automatic release point is 50% of the sentence, and extended determinate sentences (EDS), for which the earliest point of release is two-thirds of the sentence.

There are two key factors which help to explain the difference in time served in custody. Men tend to be convicted of more serious offences attracting longer custodial sentences. This means that women are more likely to be eligible for early release under the home detention curfew (HDC) scheme, which allows release up to 135 days before the halfway point of the sentence and is limited to offenders sentenced to less than four years who pass a risk assessment. The data in these tables also includes time served following recall to prison from licenced supervision. Recalled men tend to be serving longer sentences (12 months or more) and will generally serve longer after recall than recalled women, who tend to be serving less than 12 months.