@FreshPackFrank asks
I know I bought a card but can't find what I paid. Do I just use today's value?
Jeff answers
I'd mark the purchase amount unknown until you find a receipt or transaction record. Our app's current reference answers a different question. Don't fill a missing historical cost with a convenient present-day number; that can distort later comparisons. An honest blank is better than false precision.
— Jeff, infinitepulls.com