Raam wrote"
"We would like to measure our incoming goods rejections in parts per million."
I read that to mean he wants to record rejected incoming goods in the PPM format.
Atul, while your formula is very correct for "hypothetical" PPM's it is different than actual PPM. PPM needs to be based on quantity as well as quality. If my SQA called me to his/her office because I had a PPM of 1000 for the year based on sampling, I would ask for the hypothetical parts so I could verify them on my hypothetical CMM.
Maybe I'm too attuned to automotive methods in thinking that PPM's are just a different method of reporting actual scrap or rejects.
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Rejected parts X 1,000,000 / total parts = PPM
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