Question to the Department for Work and Pensions:

To ask the Secretary of State for Work and Pensions, how many people of pensionable age there were in Midlothian constituency at the most recent date for which figures are available.

The department does not hold the information required to answer this request. Please see below a link to a publication from the National Records of Scotland that holds data pertaining to this request.

UK Parliamentary Constituency Population Estimates (2011 Data Zone based) | National Records of Scotland (nrscotland.gov.uk)