There are quite a few problems with the Forbes 400 list, most notably it does not in fact capture the wealth of the 400 wealthiest people/families. A lot of old

There are quite a few problems with the Forbes 400 list, most notably it does not in fact capture the wealth of the 400 wealthiest people/families. A lot of old money is left off these lists because...well it's old money and they don't want the publicity. There are a bunch of other things to consider, for instance diversification of wealth has fundamentally transformed since the early 1900's and wealth management is on a completely different level than even 20 years ago, let alone 120 years ago. Not to mention the legal innovation to protect estate value that has been going on. I'll also point out that the people on that list are generally not using Fidelity, Vanguard, or Hancock as their wealth management services. They are using private family offices or firms like PDT Partners that are directly accountable to those families.