*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
19931
19940
19954
19963
19970
19988
19997
20004
20011
20022
20038
20048
20054
20063
20071
20081
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total57