*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19735
19740
19750
19760
19770
19781
19792
19800
19810
19821
19830
19840
19853
19862
19874
19887
19894
19905
19910
19920
19933
19946
199511
19969
19974
19980
19992
200010
20016
20021
20033
20040
20052
20063
200716
20084
20096
201035
201140
201227
201350
201420
201513
201626
201714
201841
20195
20200
20210
20220
Total391