*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19821
19830
19840
19850
19860
19870
19880
19892
19900
19911
19921
19931
19940
19950
19960
19970
19980
19991
20000
20010
20020
20030
20040
20054
20061
20071
200811
20093
20100
20110
20120
20130
20140
20150
20160
20170
20180
20190
20200
20210
20220
20230
20240
Total27