Go to the Bureau of Labor Statistics website. Find the number of tellers working for the first year of ATMs (1984) and then the number of tellers working for the last available data. You will see that the number of tellers has increased. This does not take into account the number of programmers, manufacturers, maintenance people, or even the people needed to fill the machine.
While you're there do a check to see how many individual band branches there were in 1984 verses how many there are in 2011. If it's anything like my neighborhood, which had 3 banks in 1984 and over 10 in 2011, I'd say that there are less tellers per bank now than there were way back when, that means a net loss of jobs if you the simple math you're advocating.