*Excludes Observations that spanned multiple years

Pre 19700
19700
19711
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19891
19904
19914
19927
19935
19943
199519
199639
199738
19988
19993
20009
20010
20024
20037
20046
20052
20066
20074
20082
20094
20101
20112
20123
20138
201411
20158
20166
20174
20180
Total219