Ummm no. They didn't change their way of reporting because of a 300% increase. They saw a "300%" increase because they had changed the way they were reporting. http://www.homeoffice.gov.uk/rds/pdfs08/hosb0708.pdf "Recorded crime increased during most of the 1980s, reaching a peak in 1992, and then fell each year until 1998/99 when the changes in the Counting Rules resulted in an increase in recorded offences (see Box 2.1 on ‘Changes in recording practices’). This was followed by the introduction of the National Crime Recording Standard (NCRS) in April 2002 which led to a rise in recording in 2002/03 and 2003/04, as the rules were bedded-in within forces. The level of police recorded crime has since fallen from 5.64 million in 2004/05 to 4.95 million offences in 2007/08"