*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
198610
19871
19881
19892
19900
19910
19924
19931
19940
19950
19961
19970
19980
19990
20000
20010
20020
20030
20041
20050
20065
20074
20082
20090
201044
201150
20128
20134
20144
20158
201612
20177
20181
Total170