*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19791
19800
19810
19820
19830
19840
19850
19862
19870
19880
19890
19900
19911
19920
19939
19940
19952
19960
19971
19980
19992
20001
20010
200214
20030
20040
20052
20060
20071
20082
20094
20100
20111
20120
20130
20140
20150
20161
20170
Total44