*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
19921
19930
19940
19950
19960
19970
19980
19991
20001
20010
20020
20030
20041
20057
20060
20076
20083
200916
201013
201121
201221
201312
20147
201510
20165
20170
Total125