*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19761
19770
19780
19790
19800
19810
19820
19832
198419
198524
19866
19870
19880
19890
19900
19910
19921
19937
199420
19952
199619
19970
19980
19990
20005
20010
20021
20036
20043
20057
20065
20074
20085
20098
20109
20117
20122
20134
20147
20158
20164
20172
20180
20190
Total188