*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19781
19790
19800
19810
19821
19836
19844
19853
19865
198752
19889
198929
199024
199125
19924
19930
19942
199548
19965
199778
199843
199966
200081
200167
200265
200342
200473
200575
200667
2007106
200831
200924
201073
201115
201273
20139
20141
20154
20160
20170
Total1211