The wealth of all of the world's billionaires rose to a high of $10.2 trillion during the pandemic, as millions of people around the world struggled to get by. Data showed that billionaires "did extremely well" during the period - with most benefiting from swings in capital markets.

A report published by Swiss bank UBS said the wealth of the world's billionaires had increased by more than 27.5% during the pandemic between April and July. Most that saw significant increases in their net worth had made big bets on stock markets when they were at their lowest.

The value of their combined fortunes exceed the previous record of $8.9 trillion in 2017. The UBS report showed that the number of billionaires had increased from 2,158 in 2017 to 2,189 this year.

"Billionaires did extremely well during the COVID crisis, not only [did] they ride the storm to the downside, but also gained up on the upside [as stock markets rebounded]," the report said.

Analysts at UBS said the ultrarich were able to take advantage of the crisis because they had the "stomach," or capacity, to take such risks. Most had bought significant stock from troubled companies following heavy selling. Meanwhile, stock of tech companies, often owned by billionaires, also dipped and rose sharply during the pandemic.  

Josef Stadler of UBS, who tracks the wealth of the world's richest individuals, said the extreme wealth accumulated by some on the list is an "ugly phenomenon" from a moral perspective. He added that most of these people's fortunes are almost impossible to comprehend and impossible to spend over several lifetimes.

Stadler said the trend in the disparity of wealth could lead to an "inflection point" which could become "socially destructive." The report said the concentration of wealth hasn't been this acute since 1905.