mouse interface. Although the PS/2 port became popular among IBM PC clones in the 1990s, the bus mouse was used until the end of PC-98. Epson clones Seiko Epson manufactured PC-9801 clones between 1987 and 1995, as well as compatible peripherals. In the 1980s, Epson's clones preceded NEC's in terms of its features such as performance and portability. In the early 1990s, Epson concentrated a line of low-priced computer which had low profit margins, but it did not sell well. This made resellers negative. Also, NEC had strong sales in the enterprise market, but Epson did not. Manufacturers of DOS/V computers began to get sales channels, and they became competitors for the PC-98 and its Epson clones. Nikkei Personal Computing magazine reported in 1992 that "NEC has various opinions inside the company about the future PC-98, and it is doubtful whether the PC-98 will continue to be the domestic standard. The decline of the 98 compatible machine business may lead to the decline of the PC-98 itself". In May 1992, Epson released a high performance machine, the PC-486GR. It has a 32-bit local bus for graphic processing and an Intel 486SX CPU running at 20 MHz, which was faster than NEC's flagship PC-9801FA, which had a 486SX running at 16 MHz. In January 1993, NEC released the 98MATE to compete with Epson's clones and DOS/V computers. From 1992 to 1994, Epson sold about 200,000 units of PC-98 clones every year. As of 1994, Epson expected only 40% growth in their PC sales despite they expected 100% growth in their peripherals sales by 1995. However, Nikkei Personal Computer magazine expected that Epson would continue manufacturing PC-98 clones for a while because NEC had kept a 50% share of the Japanese PC market. AST Research Japan released the DualStation 386 SX/16 in 1990 which was both PC-9801 and IBM PC compatible, but it failed because of poor marketing. Sharp, Sanyo and Seikosha each worked on PC-98 clones, but all gave up. An executive of Sanyo said, "NEC paid far more attention to its copyright than we had imagined. We decided that the loss of our corporate image would be greater than its profit, and cancelled the 98 compatible machine business." Software The PC-98 was primarily used for businesses and industry in Japan from 1980s to mid-1990s. As of September 1992, out of 16,000 PC-98 software applications, 60% of them were corporate business