*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
19887
19893
19904
19919
19925
19930
19940
19950
19960
19971
19980
19991
20001
20011
20020
20030
20041
20054
20060
20072
20082
20090
201039
201110
20121
20132
20141
20150
20160
20172
20180
20190
Total96