Records are not kept in the specific format required to derive the answer to this question. However, the following table provides details of the approximate number of departmental staff from the Department for Transport and relevant Departments prior to its establishment in 2002, who worked primarily on Crossrail at some point during each year since 2000 based on best estimates:
Number 2000 0 2001 0 2002 0 2003 3 2004 6 2005 15 2006 13 2007 14 2008 21 2009 10
The figures shown do not include staff numbers from Transport for London, the Department for Transport's co-sponsor in the scheme, or at Crossrail Limited (formerly Cross London Rail Links), the Project Delivery Body.