Calculating Installment Payments

[cavj1]

Hi All...

So I have a Grid with only a Grid Part. On the Grid Part I have the following items:

Total_Premium
Num_Of_Payments - Dropdown with values 1-9
Installment_Pmnt1
Installment_Pmnt2
Installment_Pmnt3
Installment_Pmnt4
Installment_Pmnt5
Installment_Pmnt6
Installment_Pmnt7
Installment_Pmnt8
Installment_Pmnt9
Difference_Calc

What I'm attempting to do is calculate the payment amounts based off of the Total Premium / Number of Payments. This part is simple. Where the challenge becomes is if the number does not divide evenly.

For Example - $1000 (Total_Premium) / 3 (Num_of Payments) you get $333.33333333333

I set the value to Round so the field displays $333.33 for the 3 payments. However this adds up to $999.99. I then added a field called Differenc_Calc that calculates the missing penny.

All of this works properly except I cannot figure out how to add the Penny back to the first payment. Since it is a client side calculation the number in the first field keeps "flashing" as it keeps running the field calculations over and over again. So this won't work: Total_Premium/Num_of_Payments + Difference_Calc

Any suggestions? I was trying to figure out a Button that runs a Javascript calculation 1 time but I'm failing at that as suck at Javascript (for now...)...that script looks like:

var totalPremium={grid.Object}.getValue('G','TOTAL_PREMIUM',{grid.RowNumber});
var numPayments={grid.Object}.getValue('G','NUM_OF_PAYMENTS',{grid.RowNumber});
var newPayment1=totalPremium/numPayments;
{grid.Object}.setValue('G','INSTALLMENT_PMNT1',{grid.RowNumber},newPayment1);

Thanks
Joe

[cavj1]

Re: Calculating Installment Payments

So after digging through what I have I think I have narrowed it down to:

var newPayment1=totalPremium/numPayments;

No idea what is wrong with that yet...

[cavj1]

Re: Calculating Installment Payments

So if I alert(newPayment1) I get NaN as the message....I'm thinking this is because the Total Premium field contains 2 decimal places but could be totally wrong...

[DaveM]

Re: Calculating Installment Payments

Generally calculating payments as you have, you would round up on the payments to 333.34 and the last one is the catch all. This has been proper procedure for Buy Here Pay Here car loans since I can remember. Amortised, it looks similar to
333.34
333.34
333.32

BHPH usually was for 1000 and payment set at 45.00 per week. = 22.22222222222++ payment periods
regz required we round to 6 decimals which come to 22.222222
we then took the .222222 against the 45.00 payment to reach the final payment number 23 that would be 10.00
45*22=990+10=1000.00
we were allowed to round up on the last sum to get exact value.

explain further: we were not allowed to have a last payment more than regular payments or it was termed a balloon note with tons of extra paperwork and a different type contract.

[cavj1]

Re: Calculating Installment Payments

Thanks Dave...I was just going to add the missing penny or so to the first payment and be done with it. I've had a real hard time doing that since client side calculations fire over and over again. When I would figure out the difference in a separate field and try to add it back to my first calculated field it goes crazy. I'm rethinking this now and I may be able to used my order of operations to do this a different way.

[DaveM]

Re: Calculating Installment Payments

BHPH required one field for payment amount and a separate field for final payment . Or calculated.


Good luck with payments. I had to write it all out myself and still match federal reg z as it pertains to the auto industry which is not the same as other industries like real estate.