*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19801
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19920
19930
19940
19950
19960
19970
19980
19990
20000
20011
20020
20030
20049
20056
20068
20075
200813
200932
201040
201116
201258
201320
201413
201519
201630
20170
Total271