The cost to ship crude oil is exploding on top of already-high oil prices, which is bad news for energy importers like China and for anyone paying for gas and diesel.

• Shipping a barrel of crude from West Africa to China now costs almost four times what it did in July.
• That is a 258% jump in tanker costs in just two months, on top of the higher price of the oil itself.
• The Strait of Hormuz has been shut for months because of the Iran conflict, forcing oil onto much longer routes.
• China and other big importers are being squeezed twice: paying more for the oil and far more to move it.
• This adds up to one of the biggest global energy shocks on record, worse than the 1970s oil crisis.

Outlook: With Hormuz still closed, shipping costs will keep pushing gas and diesel prices higher, and the strain on oil-importing countries will get worse.