(Bloomberg) It’s a secret of the vast U.S. Treasury market, a holdover from an age of oil shortages and mighty petrodollars: Just how much of America’s debt does Saudi Arabia own?

But now that question — unanswered since the 1970s, under an unusual blackout by the U.S. Treasury Department — has come to the fore as Saudi Arabia is pressured by plunging oil prices and costly wars in the Middle East.

In the past year alone, Saudi Arabia burned through about $100 billion of foreign-exchange reserves to plug its biggest budget shortfall in a quarter-century. For the first time, it’s also considering selling a piece of its crown jewel — state oil company Saudi Aramco. The signs of strain are prompting concern over Saudi Arabia’s outsize position in the world’s largest and most important bond market.

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