Year Measure 1971 870.62373 1972 920.47157 1973 956.27767 1974 986.17614 1975 1004.1825 1976 1024.20381 1977 1073.01115 1978 1084.73059 1979 1207.78627 1980 1234.36769 1981 1188.99791 1982 1200.35234 1983 1250.93627 1984 1292.80853 1985 1281.5584 1986 1323.54659 1987 1407.43581 1988 1446.52468 1989 1315.63283 1990 1299.55207 1991 1342.92674 1992 1405.10438 1993 1490.7251 1994 1569.67473 1995 1641.04316 1996 1719.66535 1997 1838.89761 1998 1957.58519 1999 2023.7356 2000 2078.28644 2001 2109.49604 2002 2003.4379 2003 2167.71982 2004 2279.29182 2005 2392.89391 2006 2357.95292 2007 2438.08991 2008 2752.09077 2009 2708.93643 2010 2847.25684 2011 2901.27352 2012 2974.69597 2013 2943.86979 2014 3052.38194