OPEC
... that the 13 member countries of OPEC account for 40 percent of worldwide oil production and 73 percent of proven oil reserves?
... that the 13 member countries of <b id="mwBxY"><a href="./OPEC" id="mwBxc" rel="mw:WikiLink" title="OPEC">OPEC</a></b> account for 40 percent of <a href="./List_of_countries_by_oil_production" id="mwBxg" rel="mw:WikiLink" title="List of countries by oil production">worldwide oil production</a> and 73 percent of <a href="./List_of_countries_by_proven_oil_reserves" id="mwBxk" rel="mw:WikiLink" title="List of countries by proven oil reserves">proven oil reserves</a>?