*Excludes Observations that spanned multiple years

Pre 19700
19700
19711
19720
19730
19741
19751
19760
19770
19780
19791
19802
19810
19820
19830
19840
19858
198611
198719
198869
198910
199020
199146
199226
199355
199424
1995100
199664
199755
19982
199942
200028
20019
20029
20031
20041
20050
20063
20071
20087
20091
20107
20116
20123
20135
20146
20155
20166
20171
20181
20190
20200
20212
Total659