*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
19883
19890
19900
19910
19924
19937
19940
199511
19960
19970
19980
19995
20001
20014
20020
20037
20042
20059
20066
200713
200810
20095
201011
201125
201220
201320
20149
20159
201622
201727
20180
Total230