*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
197246
19739
19740
19750
19760
19770
19780
19790
19800
19810
19820
19834
19844
198517
19869
19878
1988104
198923
199077
1991175
1992139
199328
19945
19950
19960
19972
19980
199946
200024
200130
20022
20031
20041
200511
20062
20071
200811
20092
20104
20117
20125
20130
20140
20154
20164
20172
20180
20190
Total807