*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
19921
19931
19940
19952
19960
19975
19981
19991
20002
20011
20021
200392
200478
200574
200620
200748
2008257
20093967
20104
201150
2012174
2013191
2014246
2015277
2016118
2017111
20189
Total5731