Taking into account 30 trading days horizon, Eni SpA is expected to under-perform the Exxon. In addition to that, Eni SPA is 2.27 times more volatile than Exxon Mobil Corporation. It trades about -0.37 of its total potential returns per unit of risk. Exxon Mobil Corporation is currently generating about -0.37 per unit of volatility. If you would invest 8,608 in Exxon Mobil Corporation on April 26, 2012 and sell it today you would lose (400.00) from holding Exxon Mobil Corporation or give up 4.65% of portfolio value over 30 days.
Diversification
Very weak diversification
Overlapping area represents amount of risk that can be diversified away by holding Eni SpA and Exxon Mobil Corp. in the same portfolio (assuming nothing else is changed)