a    Projected estimate (medium fertility variant).
b    2015
c    Refers to the population of Brussels-Capital Region and "communes" of the agglomeration and suburbs.
d    2017
e    2016
f    Data classified according to ISIC Rev. 4.
g    Estimate.
h    Calculated by the Statistics Division of the United Nations from national indices.
i    2014
j    Data refers to a 5-year period preceding the reference year.
k    Refers to foreign citizens.
l    Data as at the end of December.
m    Data refer to offences, not victims, of intentional homicide.
n    Population aged 16 to 74 years.
o    Users in the last 3 months.
p    Provisional data.
q    2004
r    Break in the time series.
s    Development Assistance Committee member (OECD).