a    Projected estimate (medium fertility variant).
b    2015
c    2017
d    2016
e    Estimate.
f    Data refers to a 5-year period preceding the reference year.
g    Including refugees.
h    Data as at the end of December.
i    2009
j    2002
k    2013
l    S&T budget instead of R&D expenditure.
m    Government only.
n    Break in the time series.
o    2004
p    2014
q    Arrivals by air.
r    The arrivals data relate only to three border posts (N'Djili airport in Kinshasa, the Luano airport in Lubumbashi, and the land border-crossing of Kasumbalesa in Katanga province).