*Excludes Observations that spanned multiple years

Pre 197013
19701
19710
19720
19731
19740
19751
19761
19770
19780
19790
19800
19810
19822
19830
19840
19852
19862
19879
19881
19894
199019
199114
199214
199315
19945
199529
19966
19975
19981
19994
20004
20017
20021
20039
200410
200519
20063
20075
20083
20092
20102
20112
20123
20131
20140
20150
20160
20170
Total220