*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19882
19890
19900
199152
199225
199354
19940
199517
19961
19972
19980
19990
20001
20010
20020
20033
20040
20052
20060
20070
20080
20090
20101
20110
20121
20131
20140
20155
20162
20172
20181
20192
20201
20210
20220
Total175