Year Mean Number of Trend Sites 10th Percentile 90th Percentile 2000 13.49091467 537 8.764068412 17.73334206 2001 13.2146508 537 8.805714286 17.11932675 2002 12.77159425 537 8.630140485 16.1953125 2003 12.31962768 537 7.952126437 16.00345238 2004 11.9846405 537 7.98746304 15.3881812 2005 12.81593173 537 7.839236453 16.64807407 2006 11.58828929 537 7.760366667 14.93367816 2007 11.88827789 537 7.504167989 15.41249104 2008 10.84195769 537 7.426510417 13.6112449 2009 9.760916619 537 6.930236901 12.15560345 2010 9.869507642 537 6.62952381 12.99069376 2011 9.750461091 537 6.676726127 12.10313218 2012 9.135226505 537 6.641998626 11.31346352 2013 8.94824545 537 6.391344549 11.22258871