The new report comes as wealth disparity remains a hot topic in the election and a growing source of frustration for many.

In 2019, the world's richest 500 people saw their collective net worth jump by 25 percent or $1.2 trillion, according to the Bloomberg Billionaires Index published Friday.

Progressive lawmakers have recently called for tougher tax policies for the ultra-rich; Rep. called for people to "tax the rich" as Democrats argued over Sen.

Warren has made a wealth tax a centerpiece of her campaign. The proposal calls for imposing a 2 percent tax on the wealth of people with more than $50 million in assets, while those with assets more than $1 billion would face a 3 percent tax.

Sen. Bernie Sanders Bernie SandersTrump, Biden will not shake hands at first debate due to COVID-19 Sanders tells Maher 'there will be a number of plans' to remove Trump if he loses Sirota reacts to report of harassment, doxing by Harris supporters MORE (I-Vt.) has long fought against income inequality, writing in an op-ed in 2014 that it is "the issue of our time."

“We make no apologies in stating that the great moral, economic and political issue of our time is the growing level of income and wealth inequality in our nation,” Sanders wrote.

The increase in billionaires' wealth also comes in the first full year since the passage of the Republican tax law.

A report by the Congressional Research Service in May of this year said the tax law's effect was smaller on the economy than many forecasters had predicted and growth was not consistent "with the direction and size of the supply-side incentive effects one would expect from the tax changes."