*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
19891
19900
19910
19920
19930
19940
19950
19960
19970
19980
19990
20000
20010
20021
20030
20041
20059
200639
200718
200822
200929
20106
201130
20128
20132
20144
20155
201610
201718
20180
20190
Total203