Exploration: convert international-$ to local currency in articles

[paarriagadap]

Core problem

Many monetary measures in our publication (GDP, income, absolute poverty) are presented in international dollars, a hypothetical currency representing the USD's purchasing power in a given year. Both inflation and different living costs in countries make readers lose perspective of the actual value of those numbers.

Proposed solution

To create a DoD-like overlay that converts int-$ to local currency using CPI data and PPP factors. It can also use location data, as it's currently implemented in explorers.

Alternatives

An alternative implementation would be to focus this conversion only in one article (see https://github.com/owid/owid-issues/issues/1151). Users would be led to this article by mentions of international-$ in charts and articles (using the DoD currently available in the note of this chart, for example).

Context

• In collaboration with Giving What We Can, we provided the data for their How Rich Am I calculator. This calculator converts from current currency to international-$ to situate users in the global distribution. The same data would be needed to invert the process, i.e. to convert international-$ to current currency
• @danyx23 mentioned this idea in this Slack conversation, referencing previous discussions in the past.
• Note that there are two types of PPP conversion factors, for GDP and for private consumption. This can make conversions more complicated.