*Excludes Observations that spanned multiple years

Pre 19700
19700
19711
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19822
19832
19840
198510
198645
19875
198817
198924
199011
19916
19924
199323
199416
199543
19968
199728
199844
199920
20006
200121
200222
200318
200441
200596
200618
200729
200816
200918
20109
20115
20122
20132
20142
20153
201611
20172
Total630