a    The land area of Singapore comprises the mainland and other islands.
b    2017
c    2018
d    Data classified according to ISIC Rev. 4.
e    Excluding mining and quarrying.
f    Estimate.
g    2016
h    Data refers to a 5-year period preceding the reference year.
i    2015
j    Data as at the end of December.
k    Data refer to fiscal years beginning 1 April.
l    Medisave is classified as Social insurance scheme, considering that it is a compulsory payment.
m    2013
n    Population aged 15 years and over.
o    Population aged 7 years and over.
p    2014
q    2004