When did the numbers on the numerical part of keyboards change?

The phones evolved from a dial where you pushed it so many notches and it fell back and send a fixed number of pulses down the line moving a stepper motor to change where the next wire was. It made sense to put the one first. When they went to a keypad it made sense to put the one first because it was first on the dial.

The computer keypad came from adding machines so that people in the 60s could use the keypad just like adding machines. Adding machines evolved from old mechanical adding machines where you set the numbers with levers and then pulled a large handle down and towards you. Every position past the lever cleared advanced the gear one spot. 9 was therefore at the top so that as you passed everything. Since 9 was at the top for the old style adding machine it was kept at the top of the newer ones to keep things simple.

Both the touch-tone key pad and the all-transistor calculator were made available to the general public in the 1960s.
Calculators were arranged from the beginning so that the lowest digits were on bottom. Telephone keypads put the 1-2-3 on the top row.
http://en.wikipedia.org/wiki/Calculator copy

Both configurations descended directly from earlier prototypes.