Considering 30-days investment horizon, Petrobras Argentina SA is expected to under-perform the Chevron. In addition to that, Petrobras is 3.65 times more volatile than Chevron Corporation. It trades about -0.21 of its total potential returns per unit of risk. Chevron Corporation is currently generating about -0.32 per unit of volatility. If you would invest 10,620 in Chevron Corporation on April 26, 2012 and sell it today you would lose (734) from holding Chevron Corporation or give up 6.91% of portfolio value over 30 days.
Diversification
Good diversification
Overlapping area represents amount of risk that can be diversified away by holding Petrobras Argentina SA and Chevron Corp. in the same portfolio (assuming nothing else is changed)