Footnotes  
a    2017
b    2018
c    Estimate.
d    2016
e    Areas not elsewhere specified.
f    Data refers to a 5-year period preceding the reference year.
g    2015
h    Data as at the end of December.
i    Data revision.
j    2004
k    2008
l    2000
m    2009
n    2012
o    2014