*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19772
19780
19790
19800
19810
19820
19830
19840
19850
19860
19878
19880
19890
19906
19913
19927
19934
19942
199527
199632
199732
19985
19992
20007
20010
20025
20039
20040
20054
20063
20073
20085
20092
20100
20115
20125
20137
20145
20159
201612
20174
20180
Total215