*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
19895
19902
19912
19920
19933
19946
199550
19960
19970
19980
19991
20001
20010
20021
20033
20043
20053
200610
20076
200818
200913
201022
20117
201213
20131
20147
20150
20164
20178
20180
20196
20202
20210
20221
20230
20240
Total198