*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19811
19820
19830
19841
19850
19860
19872
19884
19892
19900
199120
19925
19930
19940
19951
19960
19970
19981
19990
20000
20010
20020
20031
20040
20052
20060
20070
20083
20091
20100
20110
20120
20130
20140
20150
20160
20170
20180
20190
20200
Total45