*Excludes Observations that spanned multiple years

Pre 19708
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19920
19930
19940
19950
19960
19971
19981
19991
20001
20011
20020
20035
20041
20057
20064
20075
20080
20092
20101
20117
20120
20130
20140
20150
20160
20170
Total45