All Sculley's innovative efforts were not enough to substantially improve Apple's bottom line, and he was replaced as CEO in 1993 by company president Michael Spindler. Spindler continued the focus on innovation, producing the PowerMac, based on the power PC microprocessor, in 1994. Even though this combination produced a significant price-performance edge over both previous Macs and Intel-based machines, the IBM clones continued- to undercut Apple's prices. Spindler's response was to allow other companies to manufacture Mac clones, a strategy that ultimately led to clones stealing 20 percent of Macintosh unit sales.