*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19752
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19906
19915
199214
19931
19946
19954
19969
19977
19984
19999
20009
20016
20029
200314
200412
200511
20061
200715
200817
20098
20102
20113
20126
20133
20140
20150
20160
20170
Total183