The traditional performance review is taking heat from all sides these days.

More than 9 in 10 managers say they're unhappy with the traditional review process, which they call "biased and unreliable," according to a Gartner study. And more than half of employees believe their annual reviews are inaccurate and say those reviews don't motivate them.

U.S. managers spend more than 210 hours each year focusing on performance management tasks, with mixed results. Is there a better way to measure employee performance without relying on managers' subjective opinions? That's where performance statistics enter the picture and can be a cornerstone of any employee evaluation process. Read more.