The U.S. economy is growing despite billions of dollars in losses during the lengthy government shutdown, Grover Norquist, president of Americans for Tax Reform, said Tuesday while discussing a Congressional Budget Office report that $11 billion was lost, with $3 billion deemed a complete loss.

"The key thing is the economy continues today to grow and we were looking at a 3 percent rate of growth for the year," Norquist told Fox Business' "Mornings With Maria."

"So, $3 billion is a big number unless you compare it to the GDP of the United States in the fourth quarter. So actually we are doing fairly well."

The shutdown had a "small impact," he continued, but there also has been "tremendous growth" for the year, Norquist continued. "The CBO needs to spend more time going back to explain why they were so wrong on all recent predictions."

Meanwhile, tax cuts are creating long-run growth, as they have made the United States competitive with the rest of the world, he said.

"By taking 35 percent down to 21 percent, we became competitive with Europe," said Norquist."We weren't even close to being competitive."

The new tax code is a "good first start" for sustaining 3 percent growth, he added.

"We also need to do something about the workforce," said Norquist. "We need more workers and frankly there's more tax reduction that needs to be done and spending restraint is very important at the end of the day."

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