More than half of those who were billionaires back in 1995 no longer hold that status today, finds a new report published on Tuesday by Zurich-based UBS Group AG and global consulting firm PwC.

According to the UBS/PwC billionaire report, only 44% of billionaires 20 years ago are still billionaires today. In 1995, the report counted 289 billionaires. From this group, only 126 remain today, the report says, with the others dropping off the list due to death, family dilution or business failures. The report “shows that great wealth is very volatile,” UBS and PwC say in a statement.

However, over the same period, 1,221 new billionaires were created bringing the total number to 1,347 billionaires in 2014, the UBS/PwC billionaire report says.

The report also highlights that the population of female billionaires is growing faster than the ranks of men, as more females are driving their families’ businesses. The number of female billionaires has multiplied by 6.6 times over the last 20 years, compared to 5.2 times for men, “with Asian female entrepreneurs standing out as the main driver of this development,” the UBS/PwC statement says.

Of the 126 billionaires that have hung onto their wealth over the past 20 years, they have created US$1 trillion of wealth, growing their average wealth to US$11 billion from US$2.9 billion in 1995.

By sector, consumer & retail, technology and financial services are the industries in which these billionaires tend to operate. In contrast, the industrial, real estate and health sectors are industries where wealth has proven more fleeting.

The majority of multi-generational billionaires “created lasting legacies by keeping the initial business entirely or parts of it,” the UBS/PwC statement says.