A quality metric that measures the level of performance of a process based on the number of Defects per million opportunities (DPMO) in that process, compared to the perfection level of Six Sigma. A high Sigma Level indicates a high level of customer satisfaction which translates into favorable total sales, market share, and profitability.
Most companies perform at a Sigma Level between 2 to 3. At that level, those companies produce between 65,000 and 300,000 Defects out of every one million opportunities for a defect.
Sigma Level Conversion Table - Convert DPMO to Sigma Level to Cpk - http://www.moresteam.com/toolbox/t414.cfm