NEW YORK — Oil prices are easing on Monday and helping to calm Wall Street’s worries that inflation could get even worse. That has U.S. stock indexes rallying, though sharp swings are continuing to roil underneath the surface. The S&P 500 rose 1.5 percent following its wild July, where it swung up and down as oil prices shot higher because of the war with Iran and other worries. The Dow Jones Industrial Average was up 591 points, or 1.1 percent, as of 1:57 p.m. Eastern time, and the Nasdaq composite was 2.2 percent higher. Stocks got a lift as the price for a barrel of Brent crude sank 5 percent to $83.49. It dropped after President Donald Trump said over the weekend that he decided to hold off on new strikes against Iran at the urging of allies in the region. Brent's price careened between $72 and $102 last month as worries rose and fell about when the war with Iran would allow oil tankers to freely exit the Persian Gulf again to deliver crude to customers worldwide. The latest acquiescence by Trump on Iran helped to ease worries about the global flow of crude, and Treasury yields