SOME OF THE LARGEST retail and financial services companies in the UK have banded together to form the Demographic User Group, a body lobbying for significant additions to the next national census in 2001. Formed last May, the group comprises such companies as J Sainsbury, Abbey National, Halifax, Bank of Scotland and Whitbread. All want to see the inclusion of new questions on matters such as income and religion in a bid to milk greater commercial value from the census. In particular, the group want the census to centre around postcodes, so as to bring the information into line with other marketing data. Says DUG member and Whitbread marketing director, Martin Callingham: 'We are interested in the scope for consortium purchase of government statistics.'