Republican presidential candidates often claim they manage the economy better than the Democrats. Ted Cruz says his flat tax will create 5 million new jobs. Donald Trump promises a “really dynamic economy.” And Marco Rubio, before leaving the race, claimed that his plan to reduce the corporate tax rate would cause the economy to soar.

These pronouncements remind me of the sage words of the late New York Sen. Daniel Patrick Moynihan: “Everyone is entitled to his own opinion, but not to his own facts.”

Here are the facts: by virtually every measure of economic health—including gross domestic product growth, job creation and industrial production—the economy has performed better during Democratic administrations than during Republican ones. These are the findings of recent research by Princeton economists Alan Blinder and Mark Watson, who have studied the issue in depth.

As the ranking member of the Joint Economic Committee, I asked my staff to review these findings. They were able to update and expand upon the Blinder and Watson analysis and prepared a new fact sheet which finds that on average since World War II, real (inflation-adjusted) GDP has grown about 1.6 times faster and private-sector jobs have grown nearly 2.5 times faster under Democrats than under Republicans.

he starting point does not matter: GDP and jobs have grown faster under Democrats regardless of whether the analysis begins with President Truman, President Kennedy or President Reagan.

“The superiority of economic performance under Democrats rather than Republicans is nearly ubiquitous; it holds almost regardless of how you define success,” Blinder and Watson write in their paper, which has been accepted for publication in a forthcoming issue of the peer-reviewed economic journal American Economic Review. “By many measures, the performance gap is startlingly large,” the paper continues.

Blinder and Watson caution that many factors are out of a president’s control. These can include demographic trends, foreign economies and Federal Reserve policy. Furthermore, presidents can have only partial influence over factors that have a significant impact on the economy, such as oil prices and the rate of productivity growth. For these reasons, Blinder and Watson say the “large and significant” gap between economic performance under Democrats and Republicans is predominantly due to facts that “might be considered blends of good policy and good luck.”

On the other hand, sometimes presidents pursue policies that inadvertently have negative effects on the economy. For example, as Blinder has written: “the fact that we entered several wars in the gulf area (the latest in 2003) under Republican presidents, thereby driving up oil prices, was not just luck—it was policy, though not economic policy.”

Of course, no one can have a crystal ball to know exactly how the economy will evolve in the future. But because Republicans cite their superior ability to manage the economy as a primary reason they should control the White House, I think the American people should know the facts.

Rep. Carolyn B. Maloney, a Democrat, represents Manhattan, Queens and Brooklyn.