Each new report contains dozens of statistics on different sectors of the economy, creating plenty of scope to cherry-pick the figures that best fit a particular narrative. The main constraint on political spin appears to be avoiding untruths likely to earn the ire of fact-checkers. Mr. Trump’s evident propensity to repeat outright falsehoods may make him an exception to this rule.

Because the state of the economy usually evolves slowly, and its effect is seen across a range of indicators, a good rule is to discount any narrative built on the latest monthly number. Far better to look for persistent trends across many data sources.

Much of the best interpretation of economic conditions comes from financial firms that bet millions based on their own assessments. The profit motive appears to be keeping them honest. Their analyses — which are collected in the Federal Reserve Bank of Philadelphia’s Survey of Professional Forecasters — provide a useful crosscheck on government forecasts. These private-sector forecasters expect medium-run economic growth of around 2 percent, even as the president’s budget is premised on 3 percent growth.

But even private-sector forecasters are no match for hundreds of economists employed by the Federal Reserve. While all economic forecasts are — to be generous — imperfect, historical analyses show the Fed’s forecasts have been less imperfect than the rest.

Many economic debates center on the consequences of new policies, like repealing Obamacare, rewriting the tax code or changing priorities for spending.

The Congressional Budget Office is an important institution at such moments, both because it is insulated from political pressures and because it has deep expertise. It’s a nonpartisan scorekeeper whose job is to advise Congress about the likely effects of its proposals. The director is appointed by Congress, but beyond that, staff members are career numbers crunchers. (I serve on the C.B.O.’s Panel of Economic Advisers, a board of outside experts.)

A typical C.B.O. “score” is based on a combination of judgment and mathematical models that embody the consensus views among the broader community of economists. The Congressional Budget Office may not get the right answer, but its analysis is honest and required by law to be transparent.