*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
19890
19900
19910
19920
19930
19942
19950
19961
19970
19980
19992
20003
200114
200219
200314
200420
2005101
200628
20079
20087
200928
201025
201122
20120
20130
20140
201522
20161
20170
20180
20190
Total318