With many billionaires over 70, significant dilution of billionaire fortunes lies ahead. We will see a huge handover of wealth to their heirs, many of whom will be millennials, whose primary interests may lie outside the family business. There will also be continued volatility of wealth for business reasons. Without careful planning, many of today's fortunes will suffer substantial erosion.
In the years to come, the whole of society will benefit from this age of great wealth creation. All over the world, this generation of billionaires, and their idealistic heirs, are committing wealth to philanthropy on a greater scale than ever. Whether today's billionaires match the achievements of the Carnegies and Rockefellers, however, will depend on whether they apply their business skills to philanthropy.
What next for the gilded age?
2015's data alone does not set a trend. But 2016 and 2017 will tell whether billionaire wealth creation has levelled off in the US and Europe, and whether China's emerging entrepreneurs will continue to thrive.