UK national newspaper sales fell by 17% between 2002 and 2008

"Consider first the overall daily national newspaper market. The monthly year-on-year drop comparing December 2008 to December 2007 was 4.5%. That compares with 2% (2007-6), 3.2% (2006-5), 1.7% (2005-4), 3.2% (2004-3) and 3.8% (2003-2). Clearly, therefore, the downward trend is accelerating."
Source: Roy Greenslade in The Guardian, 9th January 2009 using figures from the ABC
(Working to produce the aggregate decline done by me - please leave a comment if you get different figures)