a    The total surface is 21 040.79 square kilometres, without taking into account the last ruling of The Hague.
b    2017
c    Refers to the urban parts of the municipalities San Salvador, Mejicanos, Soyapango, Delgado, Ilopango, Cuscatancingo, Ayutuxtepeque and San Marcos.
d    2018
e    Data classified according to ISIC Rev. 4.
f    Estimate.
g    Urban areas.
h    2016
i    Data classified according to ISIC Rev. 3.
j    2014
k    Data refers to a 5-year period preceding the reference year.
l    2015
m    Including refugees.
n    Data as at the end of December.
o    2008
p    Population aged 10 years and over.
q    Break in the time series.
r    2004