We've been dealing with the idea of annuities in a math course I'm taking, and the idea of "present value" and "future value" have come up. So basically, the "value" of an annuity before someone makes any payments is a certain value (why?) and after is another value (obviously because they've been depositing money and that money has been collecting interest as well). So I'm wonder why an annuity account has value before any payments have been made, and what is a way to calculate this? I used the formula R(1-(1+i)^-n)/i, but I'm not sure if this works.
Thank you!