*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19791
19800
19810
19821
19831
19840
19850
19861
19870
19880
19892
19903
19912
19920
19932
19940
19951
19962
19971
19980
19991
20000
20016
20021
20030
20040
20052
20060
20070
20081
20090
20103
20114
20120
20130
20140
20151
20162
20171
20180
20190
20200
Total40