Just to add ....
Having said what I have said, there seems to be a figure on page 120 of last year's MoD Annual Report which might fit the bill from your point of view ...
Look at the line for Navy Command in the table on that page and see what you come up with.
The MoD's Annual Report for the financial year 2011/2012 should become available in the next few weeks, by the way. If you look at that, you should be able to see an even more current figure for Navy Command in the equivalent table to the one I have referred to in the 2010/2011 Report.