*Excludes Observations that spanned multiple years

Pre 197013
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19831
19840
19850
19860
19870
19880
19890
19900
19910
19920
19930
19940
19950
19960
19970
19980
19990
20000
20010
20020
20031
20041
20055
200628
20075
20086
200911
20100
20115
20121
20131
20140
20150
20160
20170
Total78