About the data
3.13
Definitions
Traffic congestion in urban areas constrains eco-
associations. If they lack data or do not respond,
• Motor vehicles include cars, buses, and freight
nomic productivity, damages people’s health, and
other agencies are contacted, including road direc-
vehicles but not two-wheelers. Population figures
degrades the quality of life. In recent years own-
torates, ministries of transport or public works, and
refer to the midyear population in the year for
ership of passenger cars has increased, and the
central statistical offices. As a result, data quality
which data are available. Roads refer to motor-
expansion of economic activity has led to more
is uneven. Coverage of each indicator may differ
ways, highways, main or national roads, and sec-
goods and services being transported by road over
across countries because of different definitions.
ondary or regional roads. A motorway is a road
greater distances (see table 5.10). These devel-
Comparability is also limited when time series data
designed and built for motor traffic that sepa-
opments have increased demand for roads and
are reported. The IRF is taking steps to improve the
rates the traffic flowing in opposite directions.
vehicles, adding to urban congestion, air pollution,
quality of the data in its World Road Statistics 2010.
• Passenger cars are road motor vehicles, other than
health hazards, and traffic accidents and injuries.
Because this effort covers 2003–08 only, time
two-wheelers, intended for the carriage of passen-
The data on motor vehicles, passenger cars, and
series data may not be comparable. Another rea-
gers and designed to seat no more than nine people
road density in the table are compiled by the Interna-
son is coverage. Road density is a rough indicator of
(including the driver). • Road density is the ratio of
tional Road Federation (IRF) through questionnaires
accessibility and does not capture road width, type,
the length of the country’s total road network to the
sent to national organizations. The IRF uses a hier-
or condition. Thus comparisons over time and across
country’s land area. The road network includes all
archy of sources to gather as much information as
countries should be made with caution.
roads in the country—motorways, highways, main
possible. Primary sources are national road Biogasoline consumption as a share of total consumption is 3.13a highest in Brazil . . . Biogasoline consumption (percent of total consumption)
2000
2008
40
30
20
10
0
Brazil
France Canada Germany China
United States
Source: International Energy Agency.
. . . but the United States consumes the most biogasoline 3.13b Biogasoline consumption (thousand of tons of oil equivalent)
or national roads, secondary or regional roads, and
from petroleum products, natural gas, renewable and
other urban and rural roads. • Road sector energy
combustible waste, and electricity. Biodiesel and bio-
consumption is the total energy used in the road
gasoline, forms of renewable energy, are biodegrad-
sector, including energy from petroleum products,
able and emit less sulfur and carbon monoxide than
natural gas, combustible and renewable waste,
petroleum-derived ones. They can be produced from
and electricity. • Total energy consumption is the
vegetable oils, such as soybean, corn, palm, peanut,
country’s total energy consumption from all sources
or sunflower oil, and can be used directly only in a
(see table 3.7). • Gasoline is light hydrocarbon oil
modified internal combustion engine. Data are pro-
use in internal combustion engines such as motor
vided by the International Energy Agency.
vehicles, excluding aircraft. • Diesel is heavy oils
Data on fuel prices are compiled by the German
used as a fuel for internal combustion in diesel
Agency for International Cooperation (GIZ), from its
engines. • Fuel price is the pump price of super
global network, and other sources, including the
grade gasoline and of diesel fuel, converted from the
Allgemeiner Deutscher Automobile Club (for Europe)
local currency to U.S. dollars (see About the data).
and the Latin American Energy Organization for Latin
• Particulate matter concentration is fine sus-
America. Local prices are converted to U.S. dollars
pended particulates of less than 10 microns in diam-
using the exchange rate in the Financial Times inter-
eter (PM10) that are capable of penetrating deep
national monetary table on the survey date. When
into the respiratory tract and causing severe health
multiple exchange rates exist, the market, parallel,
damage. Data are urban-population-weighted PM10
or black market rate is used. Prices were compiled
levels in residential areas of cities with more than
in mid-November 2010, based on the crude oil price
100,000 residents. The estimates represent the
of $81 per barrel Brent.
average annual exposure level of the average urban
Considerable uncertainty surrounds estimates of 2000
2008
30
country comparisons of the relative risk of particulate
15
10
5
United States
Brazil
China
Canada France Germany
Source: International Energy Agency.
resident to outdoor particulate matter.
particulate matter concentrations, and caution should be used in interpreting them. They allow for cross-
25
0
Road sector energy consumption includes energy
Data sources
matter pollution facing urban residents. Major sources
Data on vehicles and road density are from the
of urban outdoor particulate matter pollution are
IRF’s electronic files and its annual World Road
traffic and industrial emissions, but nonanthropogenic
Statistics, except where noted. Data on road sector
sources such as dust storms may also be a substan-
energy consumption are from the IRF and the Inter-
tial contributor for some cities. Country technology
national Energy Agency. Data on fuel prices are
and pollution controls are important determinants of
from the GIZ’s electronic files. Data on particulate
particulate matter. Data on particulate matter for
matter concentrations are from Pandey and oth-
selected cities are in table 3.14.
ers’ “Ambient Particulate Matter Concentrations in Residential and Pollution Hotspot Areas of World Cities: New Estimates Based on the Global Model of Ambient Particulates (GMAPS)” (2006b).
2011 World Development Indicators
177
environment
Traffic and congestion