*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19721
19730
19740
19750
19760
19770
19780
19790
19801
19810
19820
19835
19842
19850
19860
19871
19883
198916
199021
199143
199235
199342
199424
199547
19965
199723
199820
19998
200011
200137
200219
20030
200451
200539
20062
20078
20085
200918
20100
20110
20120
20130
20140
20150
20160
20170
Total488