y states the total length of the highway system and the length
of the paved and unpaved parts.

HIV/AIDS - adult prevalence rate
This entry gives an estimate of the percentage of adults (aged 15-49)
living with HIV/AIDS. The adult prevalence rate is calculated by
dividing the estimated number of adults living with HIV/AIDS at yearend
by the total adult population at yearend.

HIV/AIDS - deaths
This entry gives an estimate of the number of adults and children who
died of AIDS during a given calendar year.

HIV/AIDS - people living with HIV/AIDS
This entry gives an estimate of all people (adults and children) alive
at yearend with HIV infection, whether or not they have developed
symptoms of AIDS.

Household income or consumption by percentage share
Data on household income or consumption come from household surveys,
the results adjusted for household size. Nations use different
standards and procedures in collecting and adjusting the data. Surveys
based on income will normally show a more unequal distribution than
surveys based on consumption. The quality of surveys is improving with
time, yet caution is still necessary in making inter-country
comparisons.

Hydrographic data codes
see Data codes

Illicit drugs
This entry gives information on the five categories of illicit drugs -
narcotics, stimulants, depressants (sedatives), hallucinogens, and
cannabis. These categories include many drugs legally produced and
prescribed by doctors as well as those illegally produced and sold
outside of medical channels.
Cannabis (Cannabis sativa) is the common hemp plant, which
provides hallucinogens with some sedative properties, and includes
marijuana (pot, Acapulco gold, grass, reefer), tetrahydrocannabinol
(THC, Marinol), hashish (hash), and hashish oil (hash oil).
Coca (mostly Erythroxylum coca) is a bush with leaves that contain
the stimulant used to make cocaine. Coca is not to be confused with
cocoa, which comes from cacao seeds and is used in making chocolate,
cocoa, and cocoa butter.
Cocaine is a stimulant derived from the leaves of the coca bush.
Depressants (sedatives) are drugs that reduce tension and anxiety
and include chloral hydrate, barbiturates (Amytal, Nembutal, Seconal,
phenobarbital), benzodiazepines (Librium, Valium), methaqualone
(Quaalude), glutethimide (Doriden), and others (Equanil, Placidyl,
Valmid).
Drugs are any chemical substances that effect a physical, mental,
emot