Last update: · A tool for converting intervention costs across currencies and price years
This ‘Intervention Cost Converter’ (v2.1.2, last update: ) is an open access web-based tool for converting intervention costs across currencies and price years: it adjusts estimates of cost expressed in one currency and price year to a specific target currency and price year. It suits costs from any sector, including health care, public health, education, social welfare and international development, because it uses economy-wide price indices and purchasing power parities. It applies the three methods of Turner et al. (2019), Value in Health 22(9):1026–1032; the default, Method 2 with PPP and the GDP deflator, is the computation of the CCEMG–EPPI Cost Converter.
Before using the tool, please read the ‘Information for users’, located beneath the tool on this web page, or the How to use page.
To use the tool, please enter and select your data using Steps 1–6, below. The further options keep their defaults unless you change them.
Each row follows one method from the reported amount to the result, like Figures 1 and 2 of Turner et al. Boxes are amounts; arrows are the rate or inflation factor applied. Values marked projected lie beyond the data.
Every rate and index behind the result. Type over a value to use your own, for example a figure from the study itself or a health-sector price index; clear the box to go back to the data. Take both years of an index from the same source, because index bases differ between sources.
The inflation used for each price index after its last year of data. Type an annual rate to replace it, for example an inflation target; clear the box to return to the setting under Years after the data.
Turner et al. suggest reporting adjusted costs in US$ and/or international dollars as well as the local currency. This table gives all of them with the current settings.
This web-based tool adjusts estimates of costs from their original currency and price year to a target currency and/or price year. The price indices (GDP deflator or consumer price index) and purchasing power parities for GDP cover the whole economy, so the tool can be used for intervention costs in any sector, not only health care. Where a sector-specific price index exists (for example a health-sector deflator), it can be typed under Values used. A step-by-step guide with worked examples is on the How to use page.
The current version of this tool is . Changes between versions are listed in the changelog. Cite the version and data vintage shown at the top of the page.
The tool computes each cost in up to three ways, following Turner et al. (2019). With C the cost in country S's currency at year-t0 prices and V the result in currency T at target-year t1 prices:
r: local currency per US$ (market) or per I$ (PPP). P: GDP deflator or CPI. s: tradable share. For US$ and I$, rT = 1 and PT is the US index.
Method 1 converts first, at the price-year rate, then inflates with US prices (or the target country's prices). It suits tradable resources such as imported drugs and equipment.
Method 2 is a two-stage computation, as in the CCEMG–EPPI Cost Converter. Stage 1 adjusts the original estimate of cost from the original price year to the target price year, using the original country's price index (the implied inflation factor, IIF). Stage 2 converts the price-year adjusted cost from the original currency to the target currency, using PPP values (or exchange rates) for the target year (the implied conversion factor, ICF). With PPP and the GDP deflator this is the default and the final result.
Method 3 treats a tradable share with Method 1 and the rest with Method 2. Turner et al. recommend it when the cost can be split.
Which to choose. With local inflation above about 15–20% a year, Kumaranayake (2000) advises working in US$ (Method 1). For high-income settings, Turner et al. advise reporting in the local currency with local inflation.
Price and target years run to 2037. After a country's last year of World Bank data, its price index follows the IMF World Economic Outlook inflation forecasts (or its own 5-, 10- or 20-year average), exchange rates follow the inflation gap against the US, and PPP factors follow the GDP-deflator gap. Projected values are displayed in red type; results that use them are rounded to 3 significant figures, and can be recomputed with your own rates.
Indices, exchange rates and PPP factors come from the World Bank, the OECD and the IMF (listed below). Every money value is in the country's current currency unit for every year: exchange rates published in an older unit (pre-euro, Bulgaria, Venezuela, Zimbabwe) are re-expressed, and an automatic check confirms that exchange rates and PPP factors agree with GDP in local currency and US$. Deflator base years differ by country but only within-country ratios are used. Statistical agencies revise past values, so results can differ slightly from published studies that used older releases.
Excel workings. Every calculation on this page is repeated as Excel formulas, with the data, so anyone can check a result: Cost_Converter_Workings.xlsx.
Code MIT licence; data CC BY 4.0 from the sources above. Source code, tests and changelog.
From a single cost to a full list, with the worked examples of Turner et al. (2019). Every field in the calculator also has an i button that explains it in place.
Costs from different years and countries cannot be compared directly: prices rise, and currencies change in value. The calculator restates a cost in the prices of one base year and in one currency, in the three ways set out by Turner et al. (2019), and shows every rate and index it uses so you can check and report the result.
The defaults suit a systematic review: international dollars, the linked GDP deflator, and Method 2 as the main result (the CCEMG–EPPI approach), with Methods 1 and 3 as sensitivity analyses.
| Method | What it does | Use it when | Watch out for |
|---|---|---|---|
| Method 1 | Converts at the price-year rate, then applies US (or output-country) inflation | Most resources are tradable, or local inflation is above about 15–20% a year | Understates local staff and service costs when local inflation runs above US inflation |
| Method 2 | Applies local inflation, then converts at the base-year rate | Most resources are nontradable: salaries, buildings, local services. The CCEMG–EPPI default with PPP | Overstates imported items when local inflation runs above US inflation |
| Method 3 | Tradable share through Method 1, the rest through Method 2 | An ingredients-based costing shows which items were imported | Needs a split that published studies often do not report |
If you cannot split the cost, Turner et al. suggest Method 1 when tradable resources dominate and Method 2 when nontradable resources dominate. The gap between the methods grows with the gap between local and US inflation. Choose the method reported as the final result under the further options; the other two are labelled sensitivity analyses.
VND 1,000,000 incurred in Vietnam in 2006, wanted in US$ at 2016 prices, 20% tradable.
US$ 73.05 · 107.59 · 100.68
The button enters the paper's rates and indices under Values used. With today's World Bank data Method 2 gives about US$ 104.36: the linked GDP deflator rises × 2.29 from 2006 to 2016, against the paper's 2.36. The standard series gives × 2.91 (US$ 132.50) because it counts Vietnam's 2010 rebasing of the national accounts as inflation.
A study reports US$ 100 for Vietnam in 2006; you want 2016 US$. In Step 1 choose in US$ (study converted). The calculator converts back to VND 1,599,425 at the 2006 rate, applies Vietnamese inflation for Method 2, and converts at the 2016 rate (Figure 4 of the paper).
US$ 116.84 · 172.09 · 161.04
You cost a programme in India and borrow a UK unit cost of £1,200 at 2015 prices. Choose United Kingdom, 2015, then Local currency of a country: India, target price year 2024. Turner et al. (Figure 3) convert at market rates; the CCEMG–EPPI tool uses PPP. Both are offered next to the target country (converted with).
Use Values used when a study reports its own deflator or exchange rate, when you want a health-sector price index, or to reproduce a published adjustment. Type over the number; the box turns violet and is marked Your value.
World Bank data end in 2024 or 2025 for most countries. For later years the calculator projects:
Projected values are shown in red type and results are rounded to 3 significant figures, with the range from the 5- and 20-year rules. Projection assumptions lists each country's rates; type a rate to replace them. A series that stopped more than 3 years before the latest data is not projected. Projections are assumptions, not data: say so in your report.
Turner et al. ask authors to state the measure of inflation, the output currency, the adjustment method, and how costs from other settings were handled. Give the data sources and vintage, the tool version, and report the local currency too. Methods-section wording writes this for the main method, and Copy link lets readers reopen the calculation.