*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19741
19755
19761
19771
19781
19799
198011
19816
19820
19831
19846
198521
198611
198715
19882
19890
19909
19910
19922
19931
19944
19955
19963
199735
199815
199924
2000102
200122
200215
2003120
2004159
2005121
2006150
200739
200842
200943
201051
201151
201214
20136
20145
20150
20160
20170
Total1129