n officially recognized local flag. Some
disputed and other areas do not have flags.

Flag graphic: Most versions of the Factbook include a color
flag at the beginning of the country profile. The flag
graphics were produced from actual flags or the best
information available at the time of preparation. The flags
of independent states are used by their dependencies unless
there is an officially recognized local flag. Some disputed
and other areas do not have flags.

GDP: This entry gives the gross domestic product (GDP) or
value of all final goods and services produced within a
nation in a given year. GDP dollar estimates in the Factbook
are derived from purchasing power parity (PPP) calculations.
See the note on GDP methodology for more information.

GDP methodology: In the Economy section, GDP dollar
estimates for all countries are derived from purchasing
power parity (PPP) calculations rather than from conversions
at official currency exchange rates. The PPP method involves
the use of standardized international dollar price weights,
which are applied to the quantities of final goods and
services produced in a given economy. The data derived from
the PPP method provide the best available starting point for
comparisons of economic strength and well-being between
countries. The division of a GDP estimate in domestic
currency by the corresponding PPP estimate in dollars gives
the PPP conversion rate. Whereas PPP estimates for OECD
countries are quite reliable, PPP estimates for developing
countries are often rough approximations. Most of the GDP
estimates are based on extrapolation of PPP numbers
published by the UN International Comparison Program (UNICP)
and by Professors Robert Summers and Alan Heston of the
University of Pennsylvania and their colleagues. In
contrast, currency exchange rates depend on a variety of
international and domestic financial forces that often have
little relation to domestic output. In developing countries
with weak currencies the exchange rate estimate of GDP in
dollars is typically one-fourth to one-half the PPP
estimate. Furthermore, exchange rates may suddenly go up or
down by 10% or more because of market forces or official
fiat whereas real output has remained unchanged. On 12
January 1994, for example, the 14 countries of the African
Financial Community (whose currencies are tied to the French
franc) devalued their currencies by 50%. This move, of
course, did not cut the real