*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 19701020010103
1970300003
197110000010
1972700007
1973600006
1974500106
1975800008
197612002014
197712001013
197810001011
197915004019
198014001015
198117002019
198219004023
198316001017
198419000019
198519001020
198622004026
198724005029
198820003023
198920002022
199018102021
1991193019041
1992220011033
199323008031
1994251012038
1995231015039
1996190029048
1997231011035
1998240023047
199919006025
2000240011035
2001320013045
2002160026042
2003170012029
2004240012036
200525007032
2006271016044
2007272010039
2008213024048
2009110013024
2010100019029
2011240047071
2012190015034
20132209013
2014200406
2015100809
2016000000
2017000000
2018000000
Total87715041501307