# How do i use this formula to find the YTM of a step up bond?

I'm trying to find the YTM for a step up bond that trades at par value, how do I use this formula? Since the par value and sale price is the same, and coupon payment is different each payment.

• Not only do SSB cohpons step up: SSBs are alao floaters, whose coupons are based on the average government bond yields in prior month; and they're puttable at par. I'm skeptical that a yield of a floater is very useful. Sep 4 at 12:25
• I'm hoping to count the yield for different maturity dates, hence this situation. but how do I calculate it? Sep 5 at 0:51
• You can observe the Singapore Government Securities (SGS) yield curve, read off what the market thinks the SGS yields wil be on SSB reset dates, and from those yields project the SSB coupons. So, your cash flows are: you pay par now, since SSBs always trade att par; you receive some projected coupons; and you receive par at maturity. There is no closed form for the yield, but you use a numerical solver to find the internal rate of return that makes all the cash flows add up to 0. Note that this SSB yield will change whenever the SGS curve changes. Sep 5 at 1:33