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Data on stops and account are collected by police force area and are published in the ‘Statistics on Race and the Criminal Justice System—2006-07’ report for the first time this month
http://www.justice.gov.uk/publications/raceandcis.htm
This information is contained in the following table, but can also be found in Table 4.9 of the report.
Police force area 2005-06 2006-07 Total Avon and Somerset 7,501 8,043 15,544 Bedfordshire 11,114 7,745 18,859 Cambridgeshire 4,506 17,708 22,214 Cheshire 48,113 75,167 123,280 Cleveland 61,618 70,279 131,897 Cumbria 7,091 18,698 25,789 Derbyshire 14,960 20,159 35,119 Devon and Cornwall 2,924 3,266 6,190 Dorset 1,694 2,144 3,838 Durham 7,675 16,017 23,692 Essex 45,251 62,946 108,197 Gloucestershire 5,158 12,789 17,947 Greater Manchester 54,188 77,549 131,737 Hampshire 43,006 59,328 102,334 Hertfordshire 28,984 43,326 72,310 Humberside 11,782 30,575 42,357 Kent 12,865 14,200 27,065 Lancashire 47,673 60,742 108,415 Leicestershire 11,568 17,453 29,021 Lincolnshire 16,525 30,268, 46,793 London, City of 61,853 28,583 90,436 Merseyside 96,878 164,715 261,593 Metropolitan Police 176,278 244,571 420,849 Norfolk 5,749 9,504 15,253 Northamptonshire 12,651 24,329 36,980 Northumbria 56,446 88,361 144,807 North Yorkshire 10,261 23,688 33,949 Nottinghamshire 25,499 24,413 49,912 South Yorkshire 19,018 36,174 55,192 Staffordshire 15,985 21,154 37,139 Suffolk 5,522 6,647 = 12,169 Surrey 10,819 19,529 30,348 Sussex 78,103 90,685 168,788 Thames Valley 29,371 56,782 86,153 Warwickshire 6,806 3,857 10,663 West Mercia 17,492 20,514 38,006 West Midlands 147,861 142,998 290,859 West Yorks 88,794 104,167 192,961 Wiltshire 6,410 6,763 13,173 Dyfed Powys 28,955 27,148 56,103 Gwent 8,810 12,434. 21,244 North Wales 8,025 14,277 22,302 South Wales 38,963 48,875 87,838 England and Wales 1,400,745 1,868,570 3,269,315