*Excludes Observations that spanned multiple years

Pre 19700
19701
19710
19720
19730
19740
19750
19761
19770
19780
19790
19800
19811
19821
19832
19840
19851
198625
19871
19880
198912
19902
19912
19925
19938
19944
199529
19961
199722
19981
19996
20003
200111
200213
20030
200445
200528
20065
200710
20089
20095
201010
201131
20120
20131
20142
20151
20162
20172
Total303