Analysis of information sources in references of the Wikipedia article "History of the Nintendo Entertainment System" in English language version.
More than 10,000 VS. System units were sold by the end of 1984 alone (some put the figure as high as 20,000)
Sales were strong as soon as the NES was marketed in the U.S. in October 1985. Nintendo sold 620,000 decks in 1986, 2.9 million in 1987 and 7.8 million in 1988. Turnover of software cassettes is no less impressive: ip from 460,000 in 1985 to a staggering 46 million three years on.