Savings percentage is not a number
A GPO savings percentage is only meaningful against a defined basket, at a defined distribution point, over a defined period. Change any one of those and the number moves without anything real changing.
The only comparison that holds up is delivered landed cost on your top items, at your distribution centers, against your current invoices for the same week.
The four questions that matter
First: is pricing deviated on the items that carry your food cost, or on a long tail you rarely buy? Second: who captures the rebate, and is the split disclosed in writing?
Third: what happens to your distribution fee structure — a lower case cost with a higher delivery fee is not savings. Fourth: what is the exit? A program that requires a multi-year commitment to hold pricing is a financing decision, not a purchasing one.
What good looks like
Real programs will run a line-item bid against your actual usage file and show the delta per case, per week, per unit. They will disclose rebate economics. They will hold the price for a defined term with a defined index for movement.
On a 70-unit operator, food is typically the largest line on the P&L. A few real basis points off delivered cost outperforms most guest-facing initiatives, and it never shows up on a receipt.
Takeaways
Compare delivered landed cost on your own usage file — never a savings percentage.
Require written disclosure of rebate splits and distribution fee changes.
Deviated pricing on top-movers beats a discount on the long tail.