In May 1961, NEC finished the NEAC-1201 electronic (parametron-based) accounting machine—a forerunner of later "office computers" (small business computers specialized in office operation). This machine was based on the technology of the NEAC-1102 and 1103 large parametron computers which were previously developed for scientific and engineering computation. It was the first Japanese-made electronic accounting machine, and was developed by integrating compact magnetic drum technology with new low-power, low-frequency parametrons which were developed to greatly improve reliability. This machine used the program memory system, and for memory was equipped with a magnetic drum having a memory capacity of 120 words. Arithmetic speed was 40 milliseconds for addition/subtraction, 120 milliseconds for multiplication (12 digits x 6 digits, average), and 720 milliseconds for division (6 digit quotient, average). Capabilities were enhanced year by year, and a later model called the NEAC-1210 competed in the market with accounting machines from NCR, Olivetti and other companies. The NEAC-1210 was widely disseminated to small and mid-size companies in Japan, and was a leading machine of the era.