*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19751
19760
19770
19780
19790
19801
19810
19820
19831
19840
19851
19860
19870
19880
19890
19900
19910
19922
19936
199410
19956
19960
19971
19980
19990
20000
20011
20020
20031
20040
20051
20060
20070
200812
20092
20100
20110
20120
20130
20140
20151
20160
20170
20180
20193
20201
20211
20226
20230
20242
Total60