Year % net 1974 0.73599 1976 0.92946 1977 1.16387 1978 1.39112 1979 1.58848 1981 1.99391 1990 3.08281 1991 3.33299 1997 3.9413 1999 4.07858 2001 4.06247 2002 4.21628 2003 4.73061 2004 5.75062 2005 6.7604 2007 6.81181 2008 7.26373 2009 7.37037 2010 9.11368 2011 9.35062 2014 12.4236 2015 13.72503 2017 17.06071