Statistical registers assignments in HP RPN calculators

[Dave Britten]

Very interesting - and bewildering how much they changed up the assignments over the years.

The 80 is probably the strangest of all: there are no stat registers, everything just sits on the stack!

The 32S and 32SII do in fact have numbered registers, it's just that you don't encounter the numeric identities unless you're using indirect addressing, and the stat registers appear to only be accessible indirectly on the 32SII (according to the manuals). Nevertheless, the assignments on the 32SII appear to match the 33S:

n - 28
Σx - 29
Σy - 30
Σx^2 - 31
Σy^2 - 32
Σxy - 33