Data Cart

Your data extract

0 variables
0 samples
View Cart
PERWT
Person weight

Codes

This is a 8-digit numeric variable with 2 implied decimal places.

Description

PERWT indicates the number of persons in the actual population represented by the person in the sample.

For the samples that are truly weighted (see the comparability discussion), PERWT must be used to yield accurate statistics for the population.

NOTE: PERWT has 2 implied decimal places. That is, the last two digits of the eight-digit variable are decimal digits, but there is no actual decimal in the data.

Comparability — Index

GENERAL
Argentina
Armenia
Austria
Belarus
Bolivia
Botswana
Brazil
Canada
Chile
China
Colombia
Costa Rica
Cuba
Germany
Switzerland

Comparability — General

PERWT is available for all samples, but only some samples have weights that differ among persons (i.e., many of the samples are "flat" samples in which the use of weights is optional).

The samples for which weights must be used to generate representative statistics are:

Argentina 1980, 1990
Brazil 1970, 1980, 1991, 2000, 2010
Canada 2001, 2011
Colombia 1985, 2005
Dominican Republic 1970, 1981
Ecuador 1974
Egypt 1986, 1996
Ethiopia 1994, 2007
France 2006, 2011
India 1983, 1987, 1993, 1999, 2004, 2009
Indonesia 1971, 1976, 1980, 1985, 1990, 1995, 2005
Iran 2006, 2011
Jamaica 2001
Kenya 1969, 1979
Mexico 1995, 2000, 2010, 2015
Mongolia 1989
Mozambique 1997
Netherlands 1960, 1971, 2001
Nigeria 2006, 2007, 2008, 2009, 2010
Pakistan 1973, 1981
Palestine 1997, 2007
Panama 1980
Paraguay 2002
Philippines 1990, 2000
Puerto Rico 1990, 2000, 2005, 2010
South Africa 1996, 2001, 2007, 2011
South Sudan 2008
Spain 1981, 1991, 2011
Sudan 2008
Tanzania 1988, 2002, 2012
Thailand 1970, 1980, 1990, 2000
Uganda 1991
United States 1990, 2000, 2005, 2010
Uruguay 2006
Venezuela 1971, 1990
Vietnam 1989, 1999, 2009

For the other samples, a weight was calculated from the sampling fraction. In those samples PERWT may not yield a precise count of the actual population to the extent that the theoretical sampling fraction was imperfect.

NOTE: The 1991 Argentina sample has an alternate weight variable that must be used to create accurate statistics for some variables. See the Argentina comparability discussion.

NOTE: Egypt 1986 is a recovered sample with missing geographic areas. Weights were constructed based on village and district population totals. Detailed notes about missing areas can be found in the geographic variables for Egypt.

NOTE: Ethiopia samples of 1984 and 2007 have special weight issues. In 1984, parts of the country are missing; weights do not correct for the missing geographic areas. The 2007 Ethiopia sample includes records from both the long and short forms, but only long form records are weighted (short form records are weighted zero). See the Ethiopia comparability section.

Some samples use fractional weights (to two decimal places), while most use only whole numbers (the first 6 digits of PERWT).

NOTE: Some samples from early years are missing geographic areas. These samples include Brazil 1960, Ethiopia 1984, Haiti 1982, Indonesia 1995, Indonesia 2005, Iraq 1997, Malaysia 1970 and 1980, Pakistan 1973, and Romania 1977.

NOTE: Mexico 1995, 2000, 2010, and Mongolia 1989 have clustered sample designs.

Comparability — Argentina [top]

The 1980 and 1991 samples are weighted; the 1970 and 2001 samples are flat.

Several important variables in 1991 require the use of an alternative weight: the unharmonized variable AR1991A_0434. That alternative weight -- not PERWT -- must be used to generate accurate statistics for industry, occupation, previous residence and birthplace. Those variables have missing responses for roughly half the population, and AR1991A_0434 corrects for this.

Comparability — Armenia [top]

The samples are flat: every record represents 10 persons in the population.

Comparability — Austria [top]

The samples are flat: every record represents 10 persons in the population.

Comparability — Belarus [top]

The samples are flat: every record represents ten persons in the population.

Comparability — Bolivia [top]

All samples are flat: every record represents 10 persons in the population.

Comparability — Botswana [top]

The samples are flat: every record represents ten persons in the population.

Comparability — Brazil [top]

In 1960, the weight variable was missing from the microdata. The IPUMS weights are therefore theoretical weights based on the census design: 25 percent of households were to receive the long-form questionnaire from which the microdata sample is derived. All persons receive an equal weight corresponding to the overall sample density for the country in 1960.

In all other years, the weight varies among individuals and within households.

Comparability — Canada [top]

The 2001 and 2011 samples are weighted; the others are flat. The 2001 and 2009 samples use fractional weights.

Comparability — Chile [top]

All samples are flat: every record represents 100 (1960) or 10 (1970-2002) persons in the population.

Comparability — China [top]

The samples are flat: every record represents 100 persons in the population.

Comparability — Colombia [top]

The 1985 and 2005 samples are weighted; the others are flat. The 2005 sample uses fractional weights.

Comparability — Costa Rica [top]

All samples are flat: every record represents an equal number of persons in the population (16.7 or 10, depending on the year).

Comparability — Cuba [top]

The sample is flat: every record represents 10 persons in the population.

Comparability — Germany [top]

All samples are flat: every record represents an equal number of persons in the population.

Comparability — Switzerland [top]

All samples are flat: every record represents 20 persons in the population.

Universe

  • All persons

Availability

  • Argentina: 1970, 1980, 1991, 2001, 2010
  • Armenia: 2001, 2011
  • Austria: 1971, 1981, 1991, 2001, 2011
  • Bangladesh: 1991, 2001, 2011
  • Belarus: 1999, 2009
  • Bolivia: 1976, 1992, 2001
  • Botswana: 1981, 1991, 2001, 2011
  • Brazil: 1960, 1970, 1980, 1991, 2000, 2010
  • Burkina Faso: 1985, 1996, 2006
  • Cambodia: 1998, 2008
  • Cameroon: 1976, 1987, 2005
  • Canada: 1852, 1871, 1881, 1891, 1901, 1911, 1971, 1981, 1991, 2001, 2011
  • Chile: 1960, 1970, 1982, 1992, 2002
  • China: 1982, 1990, 2000
  • Colombia: 1964, 1973, 1985, 1993, 2005
  • Costa Rica: 1963, 1973, 1984, 2000, 2011
  • Cuba: 2002
  • Denmark: 1787, 1801
  • Dominican Republic: 1960, 1970, 1981, 2002, 2010
  • Ecuador: 1962, 1974, 1982, 1990, 2001, 2010
  • Egypt: 1986, 1996, 2006
  • El Salvador: 1992, 2007
  • Ethiopia: 1984, 1994, 2007
  • Fiji: 1966, 1976, 1986, 1996, 2007
  • France: 1962, 1968, 1975, 1982, 1990, 1999, 2006, 2011
  • Germany: 1819, 1970, 1971, 1981, 1987
  • Ghana: 1984, 2000, 2010
  • Greece: 1971, 1981, 1991, 2001, 2011
  • Guinea: 1983, 1996
  • Haiti: 1971, 1982, 2003
  • Hungary: 1970, 1980, 1990, 2001, 2011
  • Iceland: 1703, 1729, 1801, 1901, 1910
  • India: 1983, 1987, 1993, 1999, 2004, 2009
  • Indonesia: 1971, 1976, 1980, 1985, 1990, 1995, 2000, 2005, 2010
  • Iran: 2006, 2011
  • Iraq: 1997
  • Ireland: 1971, 1979, 1981, 1986, 1991, 1996, 2002, 2006, 2011
  • Israel: 1972, 1983, 1995
  • Italy: 2001
  • Jamaica: 1982, 1991, 2001
  • Jordan: 2004
  • Kenya: 1969, 1979, 1989, 1999, 2009
  • Kyrgyz Republic: 1999, 2009
  • Liberia: 1974, 2008
  • Malawi: 1987, 1998, 2008
  • Malaysia: 1970, 1980, 1991, 2000
  • Mali: 1987, 1998, 2009
  • Mexico: 1960, 1970, 1990, 1995, 2000, 2005, 2010, 2015
  • Mongolia: 1989, 2000
  • Morocco: 1982, 1994, 2004
  • Mozambique: 1997, 2007
  • Netherlands: 1960, 1971, 2001
  • Nicaragua: 1971, 1995, 2005
  • Nigeria: 2006, 2007, 2008, 2009, 2010
  • Norway: 1801, 1865, 1875, 1900, 1910
  • Pakistan: 1973, 1981, 1998
  • Palestine: 1997, 2007
  • Panama: 1960, 1970, 1980, 1990, 2000, 2010
  • Paraguay: 1962, 1972, 1982, 1992, 2002
  • Peru: 1993, 2007
  • Philippines: 1990, 1995, 2000
  • Poland: 1978, 1988, 2002, 2011
  • Portugal: 1981, 1991, 2001, 2011
  • Puerto Rico: 1970, 1980, 1990, 2000, 2005, 2010
  • Romania: 1977, 1992, 2002, 2011
  • Rwanda: 1991, 2002
  • Saint Lucia: 1980, 1991
  • Senegal: 1988, 2002
  • Sierra Leone: 2004
  • Slovenia: 2002
  • South Africa: 1996, 2001, 2007, 2011
  • South Sudan: 2008
  • Spain: 1981, 1991, 2001, 2011
  • Sudan: 2008
  • Sweden: 1880, 1890, 1900, 1910
  • Switzerland: 1970, 1980, 1990, 2000
  • Tanzania: 1988, 2002, 2012
  • Thailand: 1970, 1980, 1990, 2000
  • Trinidad and Tobago: 1970, 1980, 1990, 2000, 2011
  • Turkey: 1985, 1990, 2000
  • Uganda: 1991, 2002
  • Ukraine: 2001
  • United Kingdom: 1851a, 1851b, 1851c, 1861a, 1861b, 1871, 1881a, 1881b, 1891a, 1891b, 1901a, 1901b, 1911, 1991, 2001
  • United States: 1850a, 1850b, 1860, 1870, 1880a, 1880b, 1900, 1910, 1960, 1970, 1980, 1990, 2000, 2005, 2010
  • Uruguay: 1963, 1975, 1985, 1996, 2006, 2011
  • Venezuela: 1971, 1981, 1990, 2001
  • Vietnam: 1989, 1999, 2009
  • Zambia: 1990, 2000, 2010