*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19791
19800
19810
19820
19830
19840
19850
19860
19870
198821
19890
19900
19917
19924
19935
19940
199533
19964
19975
199812
199913
200012
200118
20021
20031
20040
20050
20063
20071
20080
20090
20102
201122
20121
20131
20140
20153
20161
20172
20180
20194
20200
20210
20220
Total178