There’s no sure way for would-be franchisees to gauge their likely success with a potential franchise. But like bettors at a racetrack, they do have a tip sheet they can use for guidance.

It’s the Small Business Administration’s annual compilation of performance data on thousands of franchisee loans it has guaranteed.

The latest report — covering loans made from Oct. 1, 2000, to Sept. 30, 2007 — is one indicator of the relative health of 500 franchises. Among other statistics, it shows how many loans were made to a franchise, the dollars disbursed, and what percentage of loans went into liquidation, something the SBA classifies as a “failure.”

Wells Fargo & Co., a major SBA lender, says it uses the data to help spot negative trends and reduce future loan losses, as well as to prospect for business. “We select new franchisers to target for sales opportunities based on the strength of their performance,” says Thomas W. Burke, senior vice president. “High delinquencies will cause us to avoid a particular franchiser.” There are several caveats to the list…