*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
19900
19910
19920
19930
19940
19950
19960
19970
19980
19990
20000
20011
20020
20030
20040
20052
20060
20070
200844
200928
201087
2011144
20121
20130
201483
2015365
2016478
2017371
201852
201949
202034
Total1739