*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19811
19820
19832
19840
19853
19867
19873
19881
19893
19903
19912
19923
19932
19947
19952
19963
19970
19983
19991
20000
20012
20020
20035
20049
200512
200612
20072
20084
20098
201010
201111
20123
20135
20143
20150
20160
20170
Total132