Since when has OPEC spelled its name with a plus at the end?
From the US Energy Information Administration:
In 2016, largely in response to dramatically falling oil prices driven by significant increases in U.S. shale oil output, OPEC signed an agreement with 10 other oil-producing countries to create what is now known as OPEC+. Among these 10 countries was the world’s third-largest oil producer in 2022, Russia, which produced 13% of the world total (10.3 million barrels per day [b/d]).
[Others include Mexico, Kazakhstan, and Oman.]