International Dollars

In order to make the monetary amounts included in this database more readily comparable, currency conversions to international dollars have been made based on data provided by the University of Pennsylvania's world table (Penn World Table)

The Penn World Table provides purchasing power parity based conversion rates (PPP rates) prices for 189 countries/territories for some or all of the years 1950-2009.

These conversions use the "international dollar" (I$), which is a hypothetical currency with the same purchasing power of goods and services in all countries. This database uses the 2009 conversion rates. The conversion rates use the price levels in the United States as baseline, which means that one US dollar equals one International Dollar.

The method of converting national currencies into international dollars using the Penn World Table PPP exchange rate is as follows:

Amount in National Currency / PPP Exchange Rate = I$ Value


300,000 ISK (Icelandic Krona)

300000/121.91 = 2460.83

= I$ 2460.83

Amounts up to I$ 1,000 have been rounded to the nearest I$ 10 and amounts up to I$ 10,000 to the nearest I$ 100. Amounts between I$ 10,000 and until I$ 999,999 have been rounded to the nearest I$ 1,000. All amounts over I$ 1,000,000 have been rounded to the nearest I$ 10,000.

In the database we have chosen to list the I$ value along with the amount in national currency in the relevant comment.

For further reading on the Penn World Table please follow this link:

Source: Alan Heston, Robert Summers and Bettina Aten, Penn World Table Version 7.0, Center for International Comparisons of Production, Income and Prices at the University of Pennsylvania, May 2011.