What it shows
Appraisal activities (records of checks) per month as shares of 100%: process checks, which control the process while it runs, against product checks, which inspect incoming, intermediate or finished product. Appraisal sets without a sub-bucket show as Uncategorized. The dashed line is the number of failures (internal and external) per 100 checks, on the right axis.
Why it matters in manufacturing
Checking the finished product finds defects after they are made; controlling the process stops many of them from being made. Counting checks rather than their cost shows where the inspection effort goes, whatever each check costs.
How to read it
Look for the dark band to grow and the light band to shrink, and for the dashed line to fall after it. Hover a month for the shares and counts. A large Uncategorized band means the split is incomplete: give those sets a sub-bucket in master data.
What good looks like
The process checks band widens month after month while the product checks band narrows, the Uncategorized band is thin, and the dashed line of failures per 100 checks comes down.