*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19861
198728
19883
19890
19900
199116
19923
19931
199410
199528
199626
199759
19981
199920
20009
200128
20023
20031
20048
20051
20060
20071
20082
20091
20101
20113
20121
20134
20140
20150
20160
20170
20181
20193
20200
20210
20220
Total263