I think that most macro indicators will be vulnerable to random changes in currency denomination, which is why (as you suggested) economists don’t look at just nominal value. If you’re tracking changes in Logini from 2007-2017 you could convert everything to 2007 Foobars, or you could use the “loaf of bread” approach and adjust for Purchasing Power Parity. PPP is the standard way to compare currencies across time and space, it’s not perfect but it gives reasonable results.
I think that most macro indicators will be vulnerable to random changes in currency denomination, which is why (as you suggested) economists don’t look at just nominal value. If you’re tracking changes in Logini from 2007-2017 you could convert everything to 2007 Foobars, or you could use the “loaf of bread” approach and adjust for Purchasing Power Parity. PPP is the standard way to compare currencies across time and space, it’s not perfect but it gives reasonable results.