How to Lie with Percentages

We’re told that a given policy will only reduce U.S. emissions by something like 1%, which sounds trivial. But total U.S. carbon emissions are 4.8 billion tons.  One percent of that is 48 million tons, which is a lot of carbon.  At the current estimate of the social cost of carbon, reducing U.S. emissions by 1% would prevent $9 billion of harm.