(NEW YORK) — The number of billionaires in the world grew by nearly 40 percent over the past five years, but in that same time total billionaire wealth decreased slightly after years of growth.By the end of 2018, there were 2,101 billionaires in the world — an increase of 589 people or 38.9 percent over the past five years — according to the annual Billionaires Insights Report from the UBS in Switzerland that explores everything there is to know about the wealth of the ultra-elite.After five years of steady growth from 2013 to 2018 when billionaire wealth grew by 34.5 percent, billionaire wealth dropped in 2018 by 4.3 percent.”The billionaire boom of the past five years has now undergone a natural correction,” Josef Stadler, the head of ultra high net worth at UBS Global Wealth Management, said in a statement on the new report.”The stronger dollar, combined with greater uncertainty in equity markets amidst a tough geopolitical environment, has created the conditions for this dip,” he added.One notable trend in this year’s report is that women are joining the billionaires club. The number of women billionaires has grown by 46 percent over the past five years, faster than the rate of men billionaires in that same period, which was 39 percent.There are currently 233 women billionaires (up from 160 in 2013). Over half of the women billionaires in Asia are self-made, according to the report.Billionaires in the tech industry saw the greatest growth compared to any other sector last year. Tech was also the only industry that saw billionaire wealth increase in 2018 — rising to $1.3 trillion.The report also looked into the so-called “billionaire effect,” or the pattern of companies controlled by billionaires to produce higher returns. The average annual returns of public billionaire-controlled companies have been nearly twice as high as the performance of other companies over the past 15 years, according to the report. The report chalks the “billionaire effect” up to personality traits such as smart risk-taking, far-sightedness, as well as a focus on business and determination.As global economic inequality rises, however, the mere existence of billionaires has become a heated issue. Copyright © 2019, ABC Audio. All rights reserved.