I do not follow - isn't it all the more amazing that poorly paid, uneducated workers without proper salaries are able to achieve this? I would measure their pe

I do not follow - isn't it all the more amazing that poorly paid, uneducated workers without proper salaries are able to achieve this? I would measure their performance by inserting random 'canary tiffins' over a period and measuring their loss percentage. You could also track some individual carriers and get a similar measure to combine into the previous metric.