It’s not entirely clear how much inflation is related to a president’s approval rating, but research does suggest that it can hurt politicians in power. A 1999 study, for instance, found that increases in unexpected inflation hurt incumbent parties’ electoral performance. And a 2010 paper showed that inflation had a significantly negative effect on Americans’ evaluations of the president. Finally, a 2013 paper found that, along with increases in the budget deficit and unemployment, an increase in inflation “cause[d] a deterioration of presidential popularity” in the United States.

But some prices are just more important than others when it comes to inflation. Consider rising gas prices: A 2016 paper found that higher gas prices had a negative effect on presidential approval, in part because Americans are constantly reminded of them. Carola Binder, a professor of economics at Haverford College who researches inflation expectations and monetary policy, told me that high gas prices are particularly likely to affect how Americans evaluate the economy.

“You literally see gas prices and big numbers as you’re driving down the road, and you also purchase it more frequently,” said Binder. “So you’re more likely to remember how much it used to cost if you saw it last week was $2 and now it’s $3.” Binder said the same isn’t true of, say, the price tag of a family vacation.

Americans who lived through the inflation of the 1970s, however, are also more likely to react negatively to steeper gas prices.