# Excel - Function to establish mortgage bond size.

Asked By brianfosterblac on 24-Apr-12 02:25 PM
```Can anyone tell me the function in excel to use to establish the mortgage bond size I can get based on the monthly payment I can afford.

I know to use PMT to do it the other way around where I can determine the monthly payment based on a bond value.```

joeu2004 replied to brianfosterblac on 24-Apr-12 05:09 PM
`Perhaps =PV(monthlyRate,numberOfMonths,-monthlyPayment)`
PJ Hooker replied to brianfosterblac on 25-Apr-12 11:15 PM
```bond size I can get based on the monthly payment I can afford.
monthly payment based on a bond value.

You can use the PV function as suggested in another reply
Ensure to divide the RATE by 12 and multiply the NPER by 12

As you may know the PV function in Excel assumes interest is
compounded discretely as in per period compounding

There are alternatives to Excel financial functions, for example,
TADXL Excel add-in for finance has the same 5 TVM functions of RATE,
NPER, PMT, PV, & FV that permit selection of compounding of interest
whether it is discrete or continuous```