*Excludes Observations that spanned multiple years

Pre 197060
197010
19714
197225
197330
1974276
1975326
1976231
197792
1978139
1979103
1980167
1981146
1982153
1983267
1984418
1985310
1986193
1987156
1988161
1989300
1990342
1991210
1992314
1993382
1994408
1995440
1996343
1997334
1998372
1999459
2000405
2001686
2002897
2003533
2004741
2005614
2006767
2007775
2008770
2009879
2010757
2011618
2012461
2013334
201427
Total16435