*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19896
19909
199122
199225
199339
199425
199546
19966
199725
199830
199925
200023
20018
200213
20033
200429
200545
200617
200716
20088
200914
20101
20110
20120
20130
20140
20150
20163
20170
Total439