HP-65 Financial Software request

[albertofenini]

Dear Dieter,

I have keyed in the program, including the RTN instruction before LBL E as pointed out in one of the latest posts.
I have double checked the listing and recorded on a card, it works but not always, let me explain.

I initialize the program with LBL E
Then I key in 40 LBL A, and then sometimes it returns 0.00, while sometimes it returns 0.03
When it returns 0.00 if I key in 50 LBL B then the program returns 0.00 and pressing C returns the right value as in the example.

However when 0.03 was returned after keying a value for LBL A, even pressing Clx, typing 50 for B will return 0.07 and C
will return a weird value.

Also, if I initialize with E, I press 40 A (cost) and then 25 C (margin desired), pressing
B returns 0 and not the selling value.

I don't want to bother you more than I already did, and I have the HP14B and 10B that have this feature,
but I would like to understand what am I doing wrong, so if you have time I will appreciate any further comment

thanks again to everyone, Alberto