*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
19872
19884
19892
19902
19911
19922
19932
19943
19956
19966
19978
19989
19994
20005
20018
20025
200310
20044
20055
20068
200711
20085
20098
20105
20115
20124
20133
20142
20150
20160
20170
Total139