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*Excludes Observations that spanned multiple years

Pre 19700
19700
19716
19721
19730
19740
19750
19760
19770
19780
19790
19800
19811
19820
19830
19841
19850
198653
1987102
1988201
198925
199048
1991121
199297
1993104
199422
1995132
199696
1997127
199810
1999104
200039
200137
200224
20031
200410
20050
20061
20072
20089
20097
20104
201111
20123
20132
20147
201512
20162
20172
20181
20190
20200
20210
Total1425