I have often referred to Keith Betty’s Preferred Share Yield Calculator – there is a permanent link in the right hand panel under “On-Line Resources”.
I have slightly modified this spreadsheet so that it will calculate yields that reset to a different rate after a given date; you may download this spreadsheet by clicking here.
Update, 2015-2-3: There’s a detailed numerical example for the use of this calculator in the post What is the Yield of HSE.PR.A?.
Update, 2015-3-26: There’s an updated version with a better layout and a 30-year maximum term (compared to the old 25-year maximum) described in the post Yield Calculator for Resets: New and Improved!.
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