*Excludes Observations that spanned multiple years

Pre 19704
19702
19710
19720
19730
19740
19750
19760
19770
19783
19790
19801
19810
19820
19830
19840
19851
19860
19870
19882
19890
19900
19911
19920
19934
19943
19950
19961
19977
19983
19991
200010
20011
20020
20031
20040
20055
20063
200711
20082
20091
20101
20112
20120
20135
20140
20150
20160
20170
Total75