*Excludes Observations that spanned multiple years

Pre 19700
19700
19711
19721
19730
19740
19750
19760
19770
19782
19791
19800
19810
19821
19830
19840
19852
19860
19871
19883
19892
199020
199144
199222
199323
199418
199514
199615
199722
19989
19994
20005
200116
20028
20032
20047
20053
20064
20071
20082
20090
20100
20110
201254
20130
20140
20150
20161
20170
Total308