*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
19880
19890
19900
19910
199211
19931
19941
19952
19962
19970
19981
19990
20002
20011
20021
20039
20045
20051
20062
20070
20088
20094
20102
20119
20121
20133
20143
201510
20164
20178
20180
Total91