Just found this from Crestmont Research:
Waiting for Average (written April 2016):
The long-term average return from the stock market is 10.1%. As Baby Boomers continue to retire, they will increasingly rely upon their investments and pensions for income. The youngest Boomers have about a decade to compound their savings into a retirement payload. Even younger Millennials have a vested interest in stock market returns for a secure retirement. So, from 2016, what length of time is needed to assure that you will receive the historical long-term average return of 10.1%?
Answer: It will NEVER happen. From today forward, investors from today will not achieve the long-term average return. Not in ten years, twenty years, fifty years, or the nearly ninety years that represent the most recognized long-term average return.