When planning for retirement, you need to account for the value of any annuities that you own. Trouble is, there’s not just one value of an annuity—there are two: present value and future ...

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Here's how to calculate the present value of a perpetual annuity that promises to pay flat or growing annual payments with helpful examples.

Below, we'll show you how to calculate the present value of a stream of free cash flows expected over several years. Image source: Getty Images.