*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19732
19740
19752
19760
19771
19780
19791
19800
19810
19820
19831
19843
19857
19860
19870
19884
19891
19900
199116
19922
19934
19945
199531
19964
19970
19982
19993
20001
20017
20020
20030
20040
20050
20067
20070
20083
20091
201010
20116
20123
20131
20143
20151
20162
20173
20185
20195
20200
20214
20228
20230
20240
Total159