*Excludes Observations that spanned multiple years

Pre 197016
19701
19710
19720
19731
19740
19751
19762
19770
19780
19790
19800
19810
19822
19830
19840
19853
19862
19879
19881
19895
199019
199114
199214
199316
19946
199530
19967
19975
19981
19994
20004
20017
20021
200310
200410
200519
20063
20075
20083
20093
20102
20112
20123
20131
20140
20150
20160
20170
20180
Total232