(Bloomberg) -- U.S. corporations are required to pay a one-time tax on their offshore profits, but don’t expect those stockpiled funds to come onshore quickly -- or ever.

Companies repatriated $169.5 billion in the second quarter, according to data released Wednesday by the Commerce Department, up from $34.9 billion a year earlier. Still, that followed a downwardly revised $294.9 billion returned in the first quarter.

Still, the numbers for the first half of the year are just a fraction of the more than $3 trillion companies are estimated to have accumulated overseas to defer U.S. taxes on the money. President Donald Trump has said, without specifying his source, that he expects more than $4 trillion to return to the U.S., which will help to create jobs and more investment.

The tax overhaul signed into law by Trump in December gave companies incentives to bring money back to the U.S. by lowering the tax rate on repatriated profits. The new rules set a one- time rate of 15.5 percent on cash and 8 percent on non-cash or illiquid assets. Previously, companies had to pay the old 35 percent corporate rate, but only if they brought the money back to the U.S.

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