a    2017
b    Refers to the population of Brussels-Capital Region and "communes" of the agglomeration and suburbs.
c    2018
d    Data classified according to ISIC Rev. 4.
e    Estimate.
f    Calculated by the UN Statistics Division from national indices.
g    2016
h    2014
i    Data refers to a 5-year period preceding the reference year.
j    2015
k    Refers to foreign citizens.
l    Data as at the end of December.
m    Data refer to offences, not victims, of intentional homicide.
n    Users in the last 3 months.
o    Provisional data.
p    2004
q    Break in the time series.
r    Development Assistance Committee member (OECD).