The defects per million opportunities. A Lean Six Sigma metric that provides the error rate of a process.
DPMO Six Sigma example: Find 60 errors for 6 critical characteristics on 20 orders in a random sample of 400 orders
Assuming there are 6 Opportunities per order (six critical characteristics), the Defects per Opportunity (DPO is calculated as:
Opportunities = (400 Orders * 6 Opportunities / Order) = 2400 Opportunities
Defects per Opportunity (DPO) = 60 Defects / 2400 Opportunities = 0.025 Defects per Opportunity
DPMO = (0.025 Defects / Opportunity) *106 Opportunities / Million Opportunities = 25,000 DPMO
This corresponds to a Sigma Level of approximately 3.45, based on Six Sigma Demystified Appendix 9.
See a cautionary note on the improper use of DPMO and Sigma Levels in the Sigma Level topic
Learn more about the Lean Six Sigma principles and tools for process excellence in Six Sigma Demystified (2011, McGraw-Hill) by Paul Keller, in his online Lean Six Sigma DMAIC short course ($249), or his online Green Belt certification course ($499).