*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
197275
197319
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19862
198732
198826
198944
199052
1991104
199222
199322
19945
19951
19967
19975
19980
199917
200048
200115
200213
20031
20041
20053
20060
20078
20087
20090
201019
201122
20122
20131
20145
20158
20161
20173
20180
Total590