Wilhelm Schickard built the first automatic calculator called the “Calculating Clock” in 1623.
But they weren’t popular until Burroughs and Felt invented their adding machine in the the late 1880s.
It was developed specifically to help with taking the U.S. census that took place during that period.
It significantly reduced counting time for the Census Bureau.
Adding machines were common office equipment until they were replaced by personal computers in the 1980s.