*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
19890
19901
19911
19920
19930
19943
19951
19967
19971
19980
19990
20000
20011
20020
20031
20042
20053
20069
20071
200841
200937
201030
201111
201213
201312
201416
201513
20168
20171
20181
20190
20201
20212
20221
20234
20242
Total224