*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19842
19852
19860
19870
19882
19890
19908
19918
19923
19937
19943
199511
19967
19971
19980
199928
20009
200119
20021
20030
20040
20052
20062
20070
20081
20092
20100
20110
20120
20130
20141
20151
20162
20170
20182
20197
20207
202130
20227
20230
20240
Total175