Donald Trump has been anxious to take credit for the sharp run-up in stock prices since his election. While it is not clear that anything really lies behind this run-up (remember Wall Street investors are the same folks who thought AOL.com was worth $250 billion back in 2001 and that subprime mortgage backed securities were perfectly safe assets), in principle, stock prices are supposed to represent the present value of future corporate profits. If we assume that the rise in stock prices actually reflect something in the world, and not just Wall Street fantasies, then Trump has given these companies a reason to expect larger future profits.

Profits can rise for two reasons. Either they can be the same share of a larger economic pie or they can be a larger share of the same economic pie. There is no reason to believe that anyone is now expecting faster economic growth than before the election. In fact, the I.M.F. recently cut its growth projection for the U.S. If nothing Trump has done or given any indication of doing is likely to boost the U.S. growth rate then the higher expected profits must mean that investors anticipate that corporations will have a larger share of the economic pie.

There are several paths through which Trump's policies could have this effect. Most obviously, he has called for sharp reductions in the corporate tax rate. If his tax cuts go through, then after-tax corporate profits will be higher even if there is no change in before-tax profits.

A second route for higher corporate profits is by facilitating rip-offs of consumers. The Consumer Financial Protection Bureau (CFPB) was set up in large part to prevent predatory practices by the financial industry. For example, it has sought to make it more difficult for financial firms to slip conditions into contracts that no one would ever agree to if they understood them.

If the CFPB is prevented from protecting consumers then we can assume that financial firms will put more effort into ripping off their customers. This will actually reduce growth since the resources spent writing deceptive contracts could have otherwise been devoted to productive uses.

Another route in which corporate profits can be increased is by letting them destroy the environment at zero cost. For example, the Trump administration reversed an Obama administration executive order that required mining companies to restore hilltops after they did surface mining. By allowing these companies to mine areas without repairing the damage the Trump administration is saving them money. The people in the communities will suffer the consequences in the form of polluted streams and ruined forests, but this is still good news for corporate profits.

Lastly, Trump's regulatory changes might shift money from wages to profits. The most obvious example here is the plan to reverse the Obama administration's rule raising the cap under which salaried workers are automatically entitled to overtime pay. By allowing employers to require salaried workers to put in more than 40 hours a week, often without any additional pay, the Trump administration will be putting downward pressure on wages and boosting corporate profits.

For these reasons, investors might have some real cause for expecting higher corporate profits as a result of the Trump presidency. However, none of these reasons are good news for the 90 percent of the country that does not have substantial stock holdings.