*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19903
19910
19921
19934
19947
19955
19969
199719
19984
19995
20000
20010
20028
20032
20040
20051
20060
20070
20080
20090
201011
201114
20120
20130
20142
20150
20161
20170
Total97