*Excludes Observations that spanned multiple years

Pre 1970176
197010
19710
197211
19730
19740
19756
19762
19770
19782
19791
19801
19810
19820
19831
19842
19851
19861
19870
19880
19890
19900
19911
19926
19935
19945
19951
19961
19971
19981
19990
20000
20011
20020
20031
20042
200523
200628
20072
20082
200918
201022
20113
20121
20131
20141
20151
20160
20170
Total341