I am not convinced Arnott got it right. Bonds generate income and hence taxes. Generally speaking you will pay less taxes on a broadly diversified stock portfolio than a broadly diversified stock portfolio. The taxes alone will kill the long term performance of most bond portfolios. Look at the tax efficiency of Vanguard equity index funds.
Nor am convinced that Arnott chose the right indices. The right indices is the world equity performance versus the world bond performance. Not some parochial US portfolio comparison. The New Millenium have been very kind to those of us who kept our money in foreign equity markets.
Finally, the pre 20th century data isn't relevant because regulations were lacking to inspire confidence in equity markets. I wouldn't trust any data prior to the Great Depression reforms.
Why the Cheapest ETFs Aren't Necessarily the Best [View article]
It is very difficult to hedge or leverage BND.
Stock vs. Bond Performance [View article]
Nor am convinced that Arnott chose the right indices. The right indices is the world equity performance versus the world bond performance. Not some parochial US portfolio comparison. The New Millenium have been very kind to those of us who kept our money in foreign equity markets.
Finally, the pre 20th century data isn't relevant because regulations were lacking to inspire confidence in equity markets. I wouldn't trust any data prior to the Great Depression reforms.