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*Excludes Observations that spanned multiple years

Pre 197024
19701
19710
197221
197312
197430
197516
197623
197719
197821
197928
198046
198142
198273
198362
1984100
1985116
198692
198730
198834
1989141
1990130
1991114
1992124
1993168
1994123
1995161
1996113
199779
1998152
1999170
2000142
2001181
2002266
2003207
2004213
2005242
2006273
2007300
2008380
2009375
2010363
2011194
2012306
2013193
2014143
2015300
2016461
201711
20181
20191
20200
20210
Total6817