In automotive the contributing factors for excess warranty expense really boil down to either doing too many repairs or spending too much on repairs.
Therefore any system which can measure these two influences is considered a viable tool.
I think Ford's way of judging out-of-line performance has some merit. Basically, if a shop continues for 9 months (using a six-month total rolling average of expense) to be one-half (.5) standard deviation above regional or peer expense they are brought into the audit process. Same is true if they are one standard deviation above for 4 months, or over 2.0 standard deviations for any two months. (They have other rules too, but those three are the most common).
Normal deviations between dealers will exist, and you want to separate typcial swings in business from those dealers who are truly struggling with their claims.
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** Rob, Editor WD&S **
Help is only a message post away!
robc@dealersedge.com