I have to say I have no idea how you envision this working. Would there be an exchange rate configuration option in Preferences where the user would input, say, each currency’s value, normalized against the user’s preferred standard currency? Would the Airtable server itself be expected to follow world currency markets and self-correct as needed? At what interval? Based on which market?
From a practical view, accomplishing this would essentially require each field to hold two values in memory – the amount of specified currency, and the normalized value of that amount of currency – performing calculations with one, but converting to the other for display. Strictly speaking, Airtable don’t play that (except, of course, it does all the time, when the values involve pointers to records or attachments – but forget I said that!).
It seems to me a better approach might be to have an all-inclusive field that accepted – with proper leading indicator – any currencies of your choice. Using a second, hidden field – actually, a number of hidden fields – you’d then normalize entries to a common value, perform whatever manipulations are needed, and then convert back to the specified currency if needed for reporting and update. (Fields color-coded by currency is a sweet idea, though – I’d really like to see robust conditional formatting throughout Airtable.)
