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                    Closing price on 6/1/2012
                 |  |  
    
        |           
                
                    | Open | 5.50 |  
                    | High | 5.60 |  
                    | Low | 5.30 |  
                    | Volume | 166,900 |  
                    | Split-adjusted Price | 5.50 |  
                
             | 
 |  PSI Historical Quote 
            
                | Date | Change | Open | High | Low | Close | Average | Adjusted Close | Volume |  |  			
            | 6/1/2012 | +0.10 / +1.85% | 5.50 | 5.60 | 5.30 | 5.50 | 5.50 | 5.50 | 166,900 |   |  
            | 5/31/2012 | -0.30 / -5.26% | 5.70 | 5.70 | 5.40 | 5.40 | 5.40 | 5.40 | 134,700 |   |  			
            | 5/30/2012 | +0.20 / +3.64% | 5.60 | 5.80 | 5.60 | 5.70 | 5.70 | 5.70 | 258,600 |   |  
            | 5/29/2012 | -0.10 / -1.79% | 5.60 | 5.60 | 5.40 | 5.50 | 5.50 | 5.50 | 112,800 |   |  			
            | 5/28/2012 | 0.00 / 0.00% | 5.80 | 5.80 | 5.60 | 5.60 | 5.60 | 5.60 | 183,300 |   |  
            | 5/25/2012 | +0.20 / +3.70% | 5.50 | 5.60 | 5.40 | 5.60 | 5.60 | 5.60 | 186,300 |   |  			
            | 5/24/2012 | 0.00 / 0.00% | 5.50 | 5.50 | 5.10 | 5.40 | 5.40 | 5.40 | 251,700 |   |  
            | 5/23/2012 | -0.40 / -6.90% | 5.60 | 5.60 | 5.40 | 5.40 | 5.40 | 5.40 | 183,400 |   |  			
            | 5/22/2012 | +0.10 / +1.75% | 5.90 | 5.90 | 5.50 | 5.80 | 5.80 | 5.80 | 150,400 |   |  
            | 5/21/2012 | +0.30 / +5.56% | 5.40 | 5.70 | 5.20 | 5.70 | 5.70 | 5.70 | 129,300 |   |  			
            | 5/18/2012 | -0.50 / -8.47% | 5.80 | 5.80 | 5.40 | 5.40 | 5.40 | 5.40 | 475,200 |   |  
            | 5/17/2012 | -0.20 / -3.28% | 6.20 | 6.20 | 5.90 | 5.90 | 5.90 | 5.90 | 185,000 |   |  			
            | 5/16/2012 | +0.10 / +1.67% | 6.20 | 6.20 | 5.80 | 6.10 | 6.10 | 6.10 | 152,300 |   |  
            | 5/15/2012 | -0.20 / -3.23% | 6.00 | 6.30 | 5.90 | 6.00 | 6.00 | 6.00 | 397,200 |   |  			
            | 5/14/2012 | -0.40 / -6.06% | 6.60 | 6.60 | 6.10 | 6.20 | 6.20 | 6.20 | 429,400 |   |  
            | 5/11/2012 | -0.20 / -2.94% | 6.80 | 6.90 | 6.50 | 6.60 | 6.60 | 6.60 | 491,370 |   |  			
            | 5/10/2012 | -0.10 / -1.45% | 7.00 | 7.10 | 6.80 | 6.80 | 6.80 | 6.80 | 450,700 |   |  
            | 5/9/2012 | -0.10 / -1.43% | 7.00 | 7.00 | 6.80 | 6.90 | 6.90 | 6.90 | 302,000 |   |  			
            | 5/8/2012 | -0.30 / -4.11% | 7.80 | 7.80 | 7.00 | 7.00 | 7.00 | 7.00 | 528,000 |   |  
            | 5/7/2012 | +0.40 / +5.80% | 7.00 | 7.30 | 7.00 | 7.30 | 7.30 | 7.30 | 1,201,400 |   |  			
            | 5/4/2012 | +0.30 / +4.55% | 6.60 | 7.00 | 6.60 | 6.90 | 6.90 | 6.90 | 632,925 |   |  
            | 5/3/2012 | -0.10 / -1.49% | 6.60 | 6.70 | 6.30 | 6.60 | 6.60 | 6.60 | 483,600 |   |  			
            | 5/2/2012 | 0.00 / 0.00% | 7.10 | 7.10 | 6.60 | 6.70 | 6.70 | 6.70 | 753,800 |   |  
            | 4/27/2012 | +0.40 / +6.35% | 6.20 | 6.70 | 6.20 | 6.70 | 6.70 | 6.70 | 606,225 |   |  			
            | 4/26/2012 | -0.20 / -3.08% | 6.60 | 6.70 | 6.30 | 6.30 | 6.30 | 6.30 | 543,500 |   |  
            | 4/25/2012 | +0.30 / +4.84% | 6.20 | 6.50 | 6.10 | 6.50 | 6.50 | 6.50 | 624,525 |   |  			
            | 4/24/2012 | +0.20 / +3.33% | 6.00 | 6.20 | 5.80 | 6.20 | 6.20 | 6.20 | 433,100 |   |  
            | 4/23/2012 | +0.20 / +3.45% | 6.00 | 6.10 | 5.90 | 6.00 | 6.00 | 6.00 | 194,000 |   |  			
            | 4/20/2012 | -0.20 / -3.33% | 5.80 | 6.20 | 5.80 | 5.80 | 5.80 | 5.80 | 290,600 |   |  
            | 4/19/2012 | -0.30 / -4.76% | 6.00 | 6.20 | 5.80 | 6.00 | 6.00 | 6.00 | 278,200 |   |  |