This calculation was undertaken to support the rail High Level Output Specification, published in July 2007. For the small numbers of rolling stock where detailed information was not readily available at the time, the train capacity was based on the approximate mid-point of the range of similar trains where full data were available. While commuter and regional rolling stock types have similar seat and standing densities, inter-city rolling stock tends to have a lower seating density.
This information is not held by the Department for Transport, but is widely available in the specialist press.