*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19726
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19861
198735
198819
19895
199062
199172
199220
199344
19946
199510
19960
19974
19981
19990
20000
20010
20022
20032
200412
200519
20061
20070
20080
20091
20101
20111
20121
20134
20144
20155
20164
20175
2018101
20190
Total448