Some progress has been made after a lot of hard work on recruitment, retention and pre-college programs.

Yet it's unclear if the System is getting much bang out of tens of millions of bucks it spends on the effort each year.

That's why an independent audit of the 10-year effort to diversity student bodies, faculty and staff should occur.

Such an audit could clearly define how much is being spent on what. An audit could clarify which efforts seem to be working and which might not be. It could flag efforts that cost too much to justify their results.

Incoming UW-Madison Chancellor Biddy Martin suggested last week that her campus needs to become more aggressive in some of its efforts to increase its numbers of minorities. Yet she is wisely being deliberate on how to proceed.

"I think it means data gathering about what has worked and what hasn't worked so well," she told the State Journal. "And it might mean making the hard decisions to reallocate funds to different programs and try some new strategies."

An independent audit would make such a process much easier and better informed.

Provost Pat Farrell also is right that any future plan to improve diversity on campus will need more ways to measure success. Legitimate legal considerations have hampered university attempts to set specific goals. But there have to be other ways to gauge improvement.

Racial diversity is an important goal that UW System should continue to pursue. The System's student bodies, faculty and staff should include more people of different races, ethnicities, economic and social backgrounds. Workplaces the world over are becoming increasingly diverse. That means students will need to be confident and able to adapt to and thrive in diverse environments.

But spending tens of millions more on campus diversity efforts without better numbers to understand what's working well for the money and what's not -- that would be a poor use of the university's limited resources.

An independent body such as the state Legislative Audit Bureau could handle such an audit.

Increasing campus diversity in a predominantly white state such as Wisconsin is not easy. But better numbers and a detailed assessment of past efforts and costs would significantly increase the chance of future success.