An intersting (and occasionally covered on this blog) chart via FactSet on earnings and revenue growth for S&P500 constituents based on their exposures to international markets:
As the above clearly shows, globally diversified (by source of activity) companies have stronger growth in earnings and aggregate earnings. Not surprising, in general, but given the relative strength of the U.S. growth, compared to other regions' dynamics, this shows the value of income diversification.