The blended number lies.

Prime cost moves with a schedule and an order guide, and both are set one unit at a time.

The tool adds each unit’s food and beverage cost to its fully loaded labor, divides by its sales and reads every unit against the band for your service model. Fully loaded means wages, salaries, payroll taxes, benefits and workers’ compensation.

The full math, worked line by line, sits in our piece on prime cost at scale, including what happens when an owner works fifty unpaid hours a week and the labor line understates itself by three points.

One restaurant has one prime cost. With five, you already know your blended number, and it is sales-weighted, so your busiest units carry the most weight in it. The average describes a restaurant that does not exist.

That is why this tool leads with the spread. Fifteen points between your best and worst unit is an execution gap, and it sits in one restaurant. The spread tells you which restaurant to start with.

One caution on inputs: use the same period boundaries for sales, food and labor. A month of sales against four weeks of payroll will understate labor by about eight percent of itself: a true 32% reads as roughly 29.5%, in the flattering direction.

If food is the half running hot (full-service food cost typically sits between 28 and 35% of sales), the Food-Cost Install fixes it on a fixed scope: recipe costing, par, ordering and the variance tracking that holds the gain.

If it is labor, where full-service groups aim for 30 to 35% and limited-service (quick-service) groups run closer to 25 to 30%, the answer is usually the schedule rather than the wage, which our piece on cutting labor cost without cutting service works through.