*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19752
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19904
19911
19929
19932
19941
19952
19967
19977
19985
19997
20003
20014
20021
200320
200415
200514
20069
20074
200824
200914
20102
20112
20128
20134
20140
20150
20160
20170
Total171