Year Measure 1971 1022.75798 1972 841.19021 1973 969.46513 1974 963.43494 1975 1056.56231 1976 917.42317 1977 880.54311 1978 842.35748 1979 1136.72665 1980 1072.57532 1981 883.4641 1982 1042.92156 1983 1097.55455 1984 1066.15004 1985 1202.00616 1986 1450.10665 1987 1666.7227 1988 1954.59636 1989 1894.64151 1990 1972.87752 1991 2590.71614 1992 3123.62572 1993 3130.16913 1994 3576.08296 1995 3478.68776 1996 3516.72043 1997 3624.46885 1998 3795.36379 1999 3933.33548 2000 4100.35279 2001 4171.83018 2002 4211.86279 2003 4280.86381 2004 4579.38299 2005 4705.12701 2006 4860.6329 2007 4824.82313 2008 4879.65905 2009 5218.13934 2010 5212.1486 2011 5027.03188 2012 5111.76873 2013 5434.06934 2014 5759.00464