For the first time ever, 10-year bond yields track diesel prices more closely than crude, and Trump's fuel deal with Putin may be too little too late

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Diesel prices have come off their all-time highs in recent weeks, but the key industrial fuel has already moved the needle across the economy and financial markets, making affordability a more potent issue in the midterm elections.

The national average for diesel is about $6.277 per gallon, according to AAA, down from its $6.528 high but still 71% above year-ago levels. By contrast, U.S. crude oil is up 56% from a year earlier as damage to refining capacity in the Middle East and Russia has produced a sharper crunch in fuel markets.