NEW YORK — Walmart is further sweetening the perks for its U.S. store managers as it seeks to retain its leaders and attract new ones in a still competitive job market.

Nikola Corp. shares fell as much as 13% after Hindenburg Research published a report accusing the startup electric-vehicle maker of “deception” and lying about its technology.

The relentless rally in Tesla Inc. shares has driven its valuation close to the consumer product behemoth Procter & Gamble Co. as investors bet on the electric vehicle maker’s ability to dominate the automotive market of the future.