*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
19880
19890
19900
19910
19920
19930
19940
19950
19960
19970
19980
19990
20000
20010
20020
20030
20042
20050
20060
20070
20080
20090
20101
20110
20120
20132
20140
20150
20161
20170
20181
20191
20202
20213
20222
20231
20242
Total20