The Government publishes statistics on safety in custody quarterly, and updated detailed tables, including the custody type of the prisoners concerned, annually. This can be viewed on gov.uk.
(a) Information on self-harm incidents by status is available for 2015. The 2016 data will be published on 27 April 2017.
(b) In collecting information about self-harm incidents, the National Offender Management Service does not attribute intent, because it would be very difficult to do so with any degree of accuracy. Therefore the data does not distinguish incidents of attempted self-inflicted death.
(c) Information on self-inflicted deaths by status is available for 2015 and 2016.
This information can be combined with the published data on the prison population, also available on gov.uk, to calculate the relevant proportions.