Tech Compensation as a percentage of sales.

I'm wondering where some of you stand on technician pay caps as a percentage of sales. For example, if a tech was paid $15 for a 1.0 hour job that was billed at $55, then his compensation would be approximately 27% of the sale, resulting in an approximate 73% gross for the department. Excluding the additional expenses of benefits, what would be a general rule of thumb on tech pay as a percent of sales? Any input would be greatly appreciated.
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Reggie Day
Service Manager
McComb, Mississippi
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Reggie Day
Service Manager
McComb, Mississippi