*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19766
19773
19782
19790
19805
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19921
19936
19941
199523
199635
199730
19989
19995
20006
20012
20023
20032
20040
20050
20063
20070
20081
20090
20101
20114
20120
20130
20140
20150
20160
20170
Total149