*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19811
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19920
19932
19940
19951
19960
19973
19980
19990
20000
20011
20020
20030
20041
20052
200622
20077
20082
20093
2010901
201110
20122
201314
201417
20157
201614
20172
20180
Total1012