Exactly 16 years ago, Lawrence Summers and I argued on this page that modern Democratic presidents, in statistical terms, had been better for American business than their Republican counterparts. We further predicted that these superior Democratic results would continue. And we questioned why the U.S. business community, in light of this record and this outlook, remained overwhelmingly Republican.

Another presidential election is at hand, and this is the right moment to review those predictions. In the interim, we have conveniently experienced eight Republican presidential years and eight Democratic ones. Mr. Summers, as president of Harvard, cannot debate these issues now. Fortunately, the statistics speak for themselves. In fact, the long-term comparison, as well this latest 16-year one, is no contest.

According to Federal Reserve Board data, from January 1952 through June 2004 the average after-tax return on tangible capital was 4.3% under Democratic presidents and 3.2% under their Republican counterparts. ... [T]he past 16 years provide an even more stark comparison, with after-tax return on capital at 3.9% under the Clinton presidency, and just 2.5% under the Bush presidencies. Moreover, on the most basic economic measures of all -- growth, jobs and household income -- the Democratic presidential advantage over the past 16 years is enormous. On the business indices -- investment, return on capital and stock prices -- the advantage also is strong. And, of course, the Federal budget comparison is dramatic. Yes, earnings per share rose slightly more during the Bush periods, but shareholders obviously benefited more under Bill Clinton....