Accuracy of financial calculators 17BII, 19BII, and 30b

[Werner]

Using my TVM program for the 42S, I find that the monthly rate is

i% = 2.49997833318e-1

To get the Canadian annual rate, you have to calculate

c% = ((1 + i%/100)^6 - 1)*200

If you do that using ^, you get the 19BII answer.
If you calculate c% using LN1+X and E^X-1 as

c% = E^X-1(LN1+X(i%/100)*6))*200

you get the 30B answer, exactly.
All this using 12 digits only.
The 30B answer is correct to 12 digits, the others probably do not use 15 digits throughout..

Werner