*Excludes Observations that spanned multiple years

Pre 19700
19700
19711
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19822
19832
19840
198510
198645
19875
198817
198924
199011
19916
19924
199323
199416
199543
19968
199728
199844
199920
20006
200122
200222
20032256
2004709
2005760
2006470
2007585
2008246
20092029
20109
20115
20122
20133
20142
20153
201611
20172
20180
Total7451