What is Six Sigma?

Six Sigma is a methodology that attempts to standardize the concept of quality in business processes. It achieves this goal by statistically analyzing the performance of business processes. The goal of Six Sigma is to improve the performance of these processes by identifying the defects, understanding them, and eliminating the variables that cause these defects.

Six Sigma metrics give a quantitative number for the number of defects for each 1,000,000 opportunities. The term "opportunities" can be interpreted as the number of records. The perfect score is 6.0. The score of 6.0 is achieved when there are only 3.4 defects for each 1,000,000 opportunities. The score is calculated using the following formula:

• Defects Per Million Opportunities (DPMO) = (Total Defects / Total Opportunities) * 1,000,000

• Defects (%) = (Total Defects / Total Opportunities)* 100%

• Yield (%) = 100 - %Defects

• Process Sigma = NORMSINV(1-((Total Defects) / (Total Opportunities))) + 1.5

  where NORMSINV is the inverse of the standard normal cumulative distribution.