GNOME Bugzilla – Bug 103181
not-monthly repayment schedules not supported in Mortgage/Loan Druid
Last modified: 2018-06-29 20:25:36 UTC
The review page doesn't cope properly with repayment frequencies of other than a month - the calculated repayment amount is the same amount that it calculated for monthly repayments, not the lower amount that we ought to see with bi-weekly repayments, even though the dates down the side are correctly changed to reflect bi-weekly payments.
No surprise, but the auto-created transactions also have these wrong values in them. I'm upgrading the severity because of this.
Changing title, priority.
*** Bug 113598 has been marked as a duplicate of this bug. ***
*** Bug 139999 has been marked as a duplicate of this bug. ***
I get the same problem with the Mortgage/Loan Druid. I'm running GnuCash 1.8.10. I select semi-monthly payments, but the druid appears to ignore that and bases the repayment formula on a monthly frequency. Repayment Amount formula shows: pmt( interest rate / 12 : number of months remaining : loan amount : 0 : 0 ) where in the case of semi-monthly it should use: pmt( interest rate / 24 : number of payments remaining : loan amount : 0 : 0 ) I tried manually changing the contents of the formula in the "Amount" field, but If I continue to the Review page, it ignores what I entered. If I click "Back", the formula sets itself back to the first example above.
Okay, it's been 2 weeks since I commented here last, so I sat down and dug a little deeper... Looking at the source code of src/gnome/druid-loan.c, it seems that the functions that generate the payment, principal and interest formulas are hard-coded to generate the formulas based on monthly payments only, ignoring what the user has entered as their payment frequency. The functions in question are: void ld_get_pmt_formula void ld_get_ppmt_formula void ld_get_ipmt_formula Apparently, generating the formulas based on the actual desired payment frequency hasn't been implemented yet. If I were a programmer, I would probably jump in and fix this...but unfortunately I'm a network monkey. :) Josh, what plans did you have for this bug? Any timeline on a fix?
To fix it. Later. Timeline -- sometime in the next year. Gnome2 port is primary focus; loan-druid fixes -- this in particular -- would be good to have as part of a 2.0 release, but that's still a long time off. :/
Priority is marked as high, any update here? :-)
(In reply to comment #8) > Priority is marked as high, any update here? :-) I've give you three guesses. :) No, no update. It'd still be nice to have. I hope that by making the SX code simpler it'll make it easier for someone to contribute it ... but isn't that the fallacy we all operate under?
Still doesnt work with 2.2.3. I throw away my legal copy of MS Money 2005 because it doesn't support it either! Do anyone knows the formula so someone like me who do know nothing about loan formula can write some code?
Is there any update to this?
This may have been fixed with the update to Bug 647532.
I'm using 2.4.2 and this bug is still present. It's been 8 years and no movement on this? That's very surprising.
*** Bug 763579 has been marked as a duplicate of this bug. ***
I'm willing to change the code to get this fixed. However I will need some help understanding all the buttons in the assistant and how they should affect the principal and interest payment. For starters on the second page of the assistant one can choose a type of interest being "Interest Rate" or "APR (Compounded xyz)". I have found some code that converts the entered interest rate if APR was chosen into another "simple" rate. What does APR mean ? And how does this affect interest calculations ? Then on the "Loan Repayment" page of the assistant, one can see the formula used in the form pmt( "simple rate" / 12.00 : "months remaining" : "loan amount" : 0 : 0 ) It looks to me the "12.0" and "months remaining" are the parts that make the calculation assume repayments happen monthly, but it will calculate such repayment for each real interval as specified in the repayment frequency. How should these parameters be affected for other frequencies ? Let's take for example bi-monthly repayment. Would it be sufficient to take 24.0 instead of 12.0 or should "months remaining" also become "2 x months remaining" ? And is there a relation between the APR rate and the repayment frequency or can these be totally independent of each other ? I mean should the simple rate in the formula be calculated by assuming the user-entered rate to be APR (compounded whatever the repayment frequency is) ? If that would be the case would it even make sense for the user to choose the rate type) ?
Without meaning to pile on, it would be very nice to see either the non-monthly options removed from the UI, or at least some notes in the UI about them being completely broken until this is fixed. I burned a bunch of time trying to make this work recently, and I suspect I'm not the only one.
GnuCash bug tracking has moved to a new Bugzilla host. The new URL for this bug is https://bugs.gnucash.org/show_bug.cgi?id=103181. Please continue processing the bug there and please update any external references or bookmarks.