*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19757
19761
19770
19780
19791
19803
19810
19820
19830
19840
19850
19860
19870
19880
19890
19906
19915
19925
19932
19944
19956
19963
19971
19980
19995
20008
200117
20022
200316
200415
200520
20065
20073
200812
20090
201010
201114
201224
20139
20140
20150
20160
20170
Total204