*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19881
19890
19905
19910
19920
19931
19941
19951
19961
19970
19980
19994
20000
20010
20020
20030
20040
20050
20060
20070
20082
20091
201025
201123
20120
20131
20143
20152
20164
20170
201817
20190
Total93