The true cost of the opioid epidemic in 2015 was $504 billion, or roughly half a trillion dollars, according to a report released by the White House on Sunday.

The Council of Economic Advisers said the figure is more than six times larger than the most recent estimate determined by a private study carried in 2016. The study estimated prescription opioid overdose, abuse and dependence in the U.S. in 2013 would cost $78.5 billion.

The estimated number is larger because the epidemic has worsened, and overdose deaths have doubled in the past decade, the council said. In addition, previous studies did not address the number of fatalities blamed on opioids, but they focused only on prescription opioids.

“Previous estimates of the economic cost of the opioid crisis greatly underestimated it by undervaluing the most important component of the loss – fatalities resulting from overdoses,” read the White House report.

According to the U.S. Centers for Disease Control and Prevention, the number of Americans dying of an overdose involving opioids has quadrupled since 1999. In 2016, the drug crisis claimed more than 59,000 lives.

Last month, President Trump declared opioid abuse a national public health emergency, but did not take official action afterwards.

“This epidemic is a national health emergency,” President Trump said last month. “As Americans, we cannot allow this to continue. It is time to liberate our communities from this scourge of drug addiction … We can be the generation that ends the opioid epidemic. We can do it.”

An interim report by the commission stated it would take steps in the fight of the epidemic. But, in its final report earlier this month, the panel called only for more training and campaigns aimed at educating people, especially children, about the risks from picking up drugs in the first place. The report did not call for money and resources to address the crisis.