Grantham, Mayo & Van Otterloo is a Boston-based moneymanager with rouhgly 70 Billion under management. The firm focuses on high-level asset allocation.
Regularly publishes a 7 year forecast for the returns on various asset classes
These have proven to be somewhat accurate over time
Chose 7 years because historically it takes asset classes 7 years for an asset class to return to its fair value (whether starting from over or undervalued)