The Journal of Economic Inequality

, Volume 14, Issue 2, pp 141–172 | Cite as

A global count of the extreme poor in 2012: data issues, methodology and initial results

  • Francisco H. G. Ferreira
  • Shaohua Chen
  • Andrew Dabalen
  • Yuri Dikhanov
  • Nada Hamadeh
  • Dean JolliffeEmail author
  • Ambar Narayan
  • Espen Beer Prydz
  • Ana Revenga
  • Prem Sangraula
  • Umar Serajuddin
  • Nobuo Yoshida
Open Access


The 2014 release of a new set of purchasing power parity (PPP) conversion factors (PPPs) for 2011 has prompted a revision of the World Bank’s international poverty line. In revising the line, we have sought to minimize changes to the real purchasing power of the earlier $1.25 line (in 2005 PPPs), so as to preserve the integrity of the goalposts for international targets such as the Sustainable Development Goals (SDGs) and the World Bank’s twin goals – which were set with respect to that line. In particular, the new line was obtained by inflating the same fifteen national poverty lines – originally used by Ravallion et al. (World Bank Econ. Rev. 23(2): 163–184 2009) to construct the $1.25 line – to 2011 prices in local currency units, and then converting them to US dollars using 2011 PPP conversion factors. With a small approximation, this procedure yields a new international poverty line of $1.90 per person per day. In combination with other changes described in the paper, this revision leads to relatively small changes in global poverty incidence for 2011: from 14.5 % using the old method to 14.1 % using the new method. In 2012, the new reference year for the global count, we find 12.7 % of the world’s population, or 897 million people, are living in extreme poverty. There are changes in the regional composition of poverty, but they are also relatively small. This paper documents methodological decisions taken in the process of updating both the poverty line and the consumption and income distributions at the country level, including issues of inter-temporal and spatial price adjustments. It also describes various caveats and limitations of the approach taken.


Global poverty Poverty measurement Purchasing power parity 

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  1. Ahluwalia, M., Carter, N., Chenery, H.: Growth and poverty in developing countries. J. Dev. Econ. 6(3), 299–341 (1979)CrossRefGoogle Scholar
  2. Asian Development Bank: Purchasing power parities and real expenditures. Mandaluyong City, Philippines: Asian Development Bank. (2014)
  3. Balassa, B.: The PPP doctrine: a reappraisal. J. Polit. Econ. 72, 584–596 (1964)CrossRefGoogle Scholar
  4. Bamberger, M., Rugh, J., Mabry, L.: Real World Evaluation: Working under Budget, Time, Data, and Political Constraints. Sage Publications, Thousand Oaks (2006)Google Scholar
  5. Beegle, K., De Weerdt, J., Friedman, J., Gibson, J.: Methods of household consumption measurement through surveys: experimental results from Tanzania. J. Dev. Econ. 98(1), 3–18 (2012)CrossRefGoogle Scholar
  6. Biemer, P., Lyberg, L.: Introduction to Survey Quality. Wiley Series in Survey Methodology. Wiley, Hoboken (2003).
  7. Buhmann, B., Rainwater, L., Schmaus, G., Smeeding, T.: Equivalence scales, well-being, inequality and poverty: sensitivity estimates across ten countries using the Luxembourg Income Study (LIS) database. Rev. Income Wealth 34(3), 115–142 (1988)CrossRefGoogle Scholar
  8. CEDLAS and World Bank: A Guide to the SEDLAC: Socioeconomic Database for Latin America and the Caribbean. CEDLAS and The World Bank. (2010)
  9. Chandy, L., Kharas, H.: The poverty of poverty data: Brookings Institution blog, (2014)
  10. Chandy, L., Smith, C.: How poor are America’s poorest? U.S. $2 a day poverty in a global context. Global Economy and Development, Global Views, Policy Paper 2014-03. Brookings Institution, Washington (2014).
  11. Chen, S., Ravallion, M.: How well did the world’s poorest fare in the 1990s? Rev. Income Wealth 47(3), 283–300 (2001)CrossRefGoogle Scholar
  12. Chen, S., Ravallion, M.: How have the world’s poorest fared since the early 1980s? World Bank Res. Obs. 19(2), 141–169 (2004)CrossRefGoogle Scholar
  13. Chen, S., Ravallion, M.: China is poorer than we thought, but no less successful in the fight against poverty. World Bank Policy Research Working Paper, No. 4621. (2008)
  14. Chen, S., Ravallion, M.: The developing world is poorer than we thought, but no less successful in the fight against poverty. Q. J. Econ. 125(4), 1577–1625 (2010)CrossRefGoogle Scholar
  15. Cruz, M., Foster, J., Quillin, B., Schellekens, P.: Ending extreme poverty and sharing prosperity: progress and policies. Policy Research Note PRN/15/03 (2015)Google Scholar
  16. Datt, G.: Computational tools for poverty measurement and analysis. International Food Policy Research Institute, Food Consumption and Nutrition Division Discussion Paper No. 50. (1998)Google Scholar
  17. Deaton, A.: Price indexes, inequality, and the measurement of world poverty. Am. Econ. Rev. 100(1), 5–34 (2010)CrossRefGoogle Scholar
  18. Deaton, A., Aten, B.: Trying to understand the PPPs in ICP2011: why are the results so different? NBER Working Paper No 20244. (2014)
  19. Deaton, A., Kozel, V.: Data and Dogma: The great Indian poverty debate. World Bank Res. Obs. 20(2), 177–99 (2005a)CrossRefGoogle Scholar
  20. Deaton, A., Kozel, V. (eds.): The Great Indian Poverty Debate. Macmillan India Ltd, New Delhi (2005b)Google Scholar
  21. Dykstra, S., Kenny, C., Sandefur, J.: Global absolute poverty fell by almost half on Tuesday. Centre for Global Development blog: (2014)
  22. Edward, P., Sumner, A.: New estimates of global poverty and inequality: how much difference do price data really make? CGD Working Paper no. 403, Washington, DC: Center for Global Development. (2015)
  23. Gimenez, L., Jolliffe, D.: Inflation for the poor: a comparison of CPI and household survey data. Bangladesh Development Studies 37(1/2), 57–81 (2014)Google Scholar
  24. Government of India: Report of the Task Force on Projections of Minimum Needs and Effective Consumption. Planning Commission, New Delhi (1979)Google Scholar
  25. Government of India: Report of the Expert Group to Review the Methodology for Estimation of Poverty. Planning Commission, New Delhi (2009).
  26. Government of India: Press Note on Poverty Estimates, 2011–12. Planning Commission, New Delhi (2013)Google Scholar
  27. Inklaar, R., Rao, D.S.: Cross-country income levels over time: did the developing world suddenly become much richer? GGDC Research Memorandum Working Paper no. 151. (2014)
  28. James, W., Schofield, E.: Human Energy Requirements. A Manual for Planners and Nutritionists. Oxford Medical Publications, Oxford (1990)Google Scholar
  29. Jolliffe, D.: Measuring absolute and relative poverty: the sensitivity of estimated household consumption to survey design. J. Econ. Soc. Meas. 27(1–2), 1–23 (2001)Google Scholar
  30. Jolliffe, D.: Poverty, prices and place: how sensitive is the spatial distribution of poverty to cost of living adjustments? Econ. Inq. 44(2), 296–310 (2006)CrossRefGoogle Scholar
  31. Jolliffe, D., Lanjouw, P., Chen, S., Kraay, A., Meyer, C., Negre, M., Prydz, E., Vakis, R., Wethli, K.: A Measured Approach to Ending Poverty and Boosting Shared Prosperity: Concepts, Data, and the Twin Goals. Policy Research Report. The World Bank, Washington (2014)Google Scholar
  32. Jolliffe, D., Prydz, E.B.: Global poverty goals and prices: how purchasing power parity matters. Policy Research Working Paper, No. 7256. The World Bank, Washington (2015)Google Scholar
  33. Jolliffe, D., Prydz, E.B.: Estimating international poverty lines from comparable national thresholds: a robust approach for estimating relevant thresholds. Journal of Economic Inequality, this issue (2016)Google Scholar
  34. Kakwani, N.: On a class of poverty measures. Econometrica 48, 437–446 (1980)CrossRefGoogle Scholar
  35. Kakwani, N., Son, H.: Global poverty estimates based on 2011 purchasing power parity: where should the new poverty line be drawn? ECINEQ Working Paper, pp. 2015–371 (2015)Google Scholar
  36. Klasen, S., Krivobokova, T., Greb, F., Lahoti, R., Pasaribu, S., Wiesenfarth, M.: International income poverty measurement: which way now? Journal of Economic Inequality, this issue (2016)Google Scholar
  37. Kravis, I., Summers, R., Heston, A.: Real GDP per capita for more than one hundred countries. Econ. J. 88(8), 215–242 (1978)CrossRefGoogle Scholar
  38. Lakner, C., Negre, M., Prydz, E.B.: The role of inclusive growth in ending extreme poverty. paper presented at Sixth ECINEQ Meeting, July 2015 (2015)Google Scholar
  39. Lanjouw, P., Ravallion, M.: Poverty and household size. Econ. J. 105(433), 1415–1434 (1995)CrossRefGoogle Scholar
  40. Minoiu, C., Reddy, S.: Estimating poverty and inequality from grouped data: how well do parametric methods perform? Journal of Income Distribution 18(2), 160–78 (2009)Google Scholar
  41. Ravallion, M.: Measuring aggregate welfare in developing countries: how well do national accounts and surveys agree? Rev. Econ. Stat. 85(3), 645–652 (2003)CrossRefGoogle Scholar
  42. Ravallion, M.: A global perspective on poverty in India. Econ. Polit. Wkly. 43 (43), 31–37 (2008) Google Scholar
  43. Ravallion, M.: Price levels and economic growth: making sense of revisions to data on real incomes. Rev. Income Wealth 59(4), 593–613 (2013)CrossRefGoogle Scholar
  44. Ravallion, M.: An exploration of the international comparison program’s new global economic landscape. NBER Working Paper No 20338 (2014)
  45. Ravallion, M., Chen, C., Sangraula, P.: Dollar a day revisited. World Bank Econ. Rev. 23(2), 163–184 (2009)CrossRefGoogle Scholar
  46. Ravallion, M., Datt, G., Walle, D.: Quantifying absolute poverty in the developing world. Rev. Income Wealth 37(4), 345–361 (1991)CrossRefGoogle Scholar
  47. Reddy, S., Pogge, T.: How not to count the poor. In: Anand, S., Segal, P., Stiglitz, J. (eds.) Debates on the Measurement of Poverty. Oxford University Press (2008)Google Scholar
  48. Sandefur, J.: Africa rising? Using micro surveys to correct macro time series. Center for Global Development, manuscript (2013)
  49. Samuelson, P.: Theoretical notes on trade problems. Rev. Econ. Stat. 46, 145–154 (1964)CrossRefGoogle Scholar
  50. Serajuddin, U., Uematsu, H., Wieser, C., Yoshida, N., Dabalen, A.: Data deprivation: another deprivation to end. Policy Research Working Paper, No. 7252. World Bank, Washington (2015)Google Scholar
  51. Sillers, D.: Is $1.82 the new $1.25? Choosing the next international extreme poverty line. USAID Economic Brief July. USAID, Washington (2015)Google Scholar
  52. Smith, L., Dupriez, O., Troubat, N.: Assessment of the reliability and relevance of the food data collected in national household consumption and expenditure surveys. International Household Survey Network, Food and Agriculture Organization of the United Nations and World Bank. (2014)
  53. Statistics Indonesia: Number Of Poor People, Percentage of Poor People and The Poverty Line, 1970-2013’. Jakarta: Government of Indonesia, (2015)
  54. United Nations Statistics Division: Handbook on Poverty Statistics: Concepts, Methods and Policy Use. New York, NY: United Nations (2005)
  55. Villasenor, J., Arnold, B.: Elliptical Lorenz curves. J. Econ. 40(2), 327–338 (1989)CrossRefGoogle Scholar
  56. World Bank: World Development Report: Poverty. The World Bank, Washington (1990)Google Scholar
  57. World Bank: Tajikistan: Poverty Assessment. The World Bank, Washington (2009).
  58. World Bank: Bangladesh Poverty Assessment: Assessing a decade of progress in reducing poverty, 2000–2010. Bangladesh Development Series, The World Bank, Dhaka.
  59. World Bank: Purchasing Power Parities and the Real Size of World Economies: A Comprehensive Report of the 2011 International Comparison Program. The World Bank, Washington (2015a)Google Scholar
  60. World Bank: Global Monitoring Report 2015/2016: Development in an Era of Demographic Change. The World Bank, Washington (2015b)CrossRefGoogle Scholar
  61. World Bank: Technical note on latest Ghana’s poverty figures GLSS round 6: 2012-2013. Ghana Poverty Assessment 2012/13. Manuscript, forthcoming (2015c)Google Scholar

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© The Author(s) 2016

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  • Francisco H. G. Ferreira
    • 1
  • Shaohua Chen
    • 1
  • Andrew Dabalen
    • 2
  • Yuri Dikhanov
    • 3
  • Nada Hamadeh
    • 3
  • Dean Jolliffe
    • 1
    Email author
  • Ambar Narayan
    • 2
  • Espen Beer Prydz
    • 1
  • Ana Revenga
    • 2
  • Prem Sangraula
    • 1
  • Umar Serajuddin
    • 3
  • Nobuo Yoshida
    • 2
  1. 1.Development Economics Research GroupThe World BankWashingtonUSA
  2. 2.Poverty and Equity Global PracticeThe World BankWashingtonUSA
  3. 3.Development Economics Data GroupThe World BankWashingtonUSA

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