> if we slice the data up three ways to hell and back, /all/ we see is unexplainable variation It's certainly true that you can go too far, but this is a case

> if we slice the data up three ways to hell and back, /all/ we see is unexplainable variation It's certainly true that you can go too far, but this is a case where we can know a priori that the mfg date could be causing bias in the numbers they're showing, because the estimated failure rates at 5 years cannot contain data from any drives newer than 2020, whereas failure rates at 1 year can. At a minimum you might want to exclude newer drives from the analysis, e.g. exclude anything after 2020 if you want to draw conclusions about how the failure rate changes up to the 5-year mark.