*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19801
19810
19820
19830
19840
19856
19862
19875
19881
19897
199037
199126
199223
19930
19941
19950
19960
19978
19983
19996
20002
20016
20020
20030
200433
20052
20061
20076
20088
20094
20104
20119
20124
20138
20146
20157
201623
201720
20180
Total269