*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19742
19751
19760
19770
19780
19792
19804
19814
19820
19830
19840
19855
19861
19874
19880
19890
19901
19910
19920
19931
19941
19950
19961
19975
19982
19993
200064
200123
200223
200352
200456
200552
2006132
200711
200810
2009125
201076
201113
201218
20130
20144
20150
20160
20170
Total696