a    2017
b    2019
c    2018
d    Estimate.
e    2016
f    Areas not elsewhere specified.
g    Data refers to a 5-year period preceding the reference year.
h    Including refugees.
i    Refers to foreign citizens.
j    Data as at the end of December.
k    Pending a more accurate study into stateless in Iraq, the estimate of stateless persons in Iraq has been adjusted to reflect the reduction of statelessness in line with Law 26 of 2006, which allows stateless persons to apply for nationality in certain circumstances.
l    2014
m    2007
n    2005
o    2013
p    Data are as at 1 January of reporting year.
q    Population aged 15 years and over.
r    Last week.
s    Excluding business enterprise.
t    Based on R&D budget instead of R&D expenditure.
u    Excluding private non-profit.