*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19835
19840
19850
19868
19873
198815
19894
19901
199113
199228
199311
199425
199534
19967
19975
19980
19993
20000
20010
200213
20035
20040
20052
20063
20071
20086
20090
20100
20113
20120
20130
20142
20150
20160
20177
201826
201941
202023
202132
202228
202343
20242
Total399