During the war, Texaco ranked 93rd among United States corporations in the value of military production contracts. In 1947, Caltex expanded to include Texaco's European marketing operations. That same year, Texaco merged its British operation with Trinidad Leaseholds under the name Regent; it gained full control of Regent in 1956, but the Regent brand remained in use until 1968-9. In 1954, the company added the detergent additive Petrox to its "Sky Chief" gasoline, which was also souped up with higher octane to meet the antiknock needs of new cars with high-compression engines.