*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
19894
19900
19915
19924
19933
19940
19952
19963
19971
19982
199912
20000
20010
20020
20030
20040
20050
20062
20070
20081
20092
20100
20112
20120
20131
20142
20150
20160
20173
20181
20191
20202
20211
20224
20238
20241
Total67