HP 12C - 12c Platinum -- VAT amount, NET, GROSS

[2old2randr]

Interesting.

I tried the same thing but I get different results on an HP 12c+ (the one with 2 CR2032 batteries).

I did 1 ENTER, 2 ENTER, 3 ENTER, 4 to fill the stack (T=1, Z=2, Y=3, X=4). Then 0 PMT 1 n 19 i 238 FV PV. Now when I look at the stack, I find T=2, Z=3, Y=4 and X=-200.

In other words, the stack is not disturbed except to display the final result. The original, X, Y and Z values are preserved.