*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19908
19915
19929
19934
19946
19955
19969
19974
19987
19994
20002
20018
20026
200325
200427
200525
200625
200718
200851
200912
20105
20114
201212
20133
20140
20150
20160
20170
Total284