*Excludes Observations that spanned multiple years

Pre 19702
19700
19710
19720
19730
19740
19751
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19924
19931
19940
19950
19960
19970
19980
19992
20005
200110
20028
200316
20048
200511
20061
20071
20081
20093
20100
20110
20120
20130
20140
20150
20160
20170
Total74