| 
                 
                    Closing price on 3/29/2012
                 
             | 
            
                                
             | 
         
         
 
    
        
                      
                
                    | Open | 
                    9.00 | 
                 
                
                    | High | 
                    9.00 | 
                 
                
                    | Low | 
                    8.30 | 
                     
                
                    | Volume | 
                    111,400 | 
                                 
                
                    | Split-adjusted Price | 
                    5.47 | 
                 
             
            
            
                
             
         | 
        
            
            
             
                            
         | 
     
 
POT Historical Quote 
        
            
                | 
                    Date
                 | 
                
                    Change
                 |                 
                
                    Open
                 |          
                
                    High
                 |            
                
                    Low
                 |                                                 
                
                    Close
                 | 
                
                    Average
                 | 
                
                    Adjusted Close
                 |                                                 
                
                    Volume
                 |     
                
                     
                 |                                       
                             
    
        			
            | 
                3/29/2012
             | 
            
                -0.50 / -5.62%
             |             
            
                9.00
             |           
            
                9.00
             |               
            
                8.30
             |                           
            
                8.40
             | 
            
                8.55
             |                     
            
                5.47
             |                                 
            
                111,400
             |            
            
                 
             |                                       
         
    
        
            | 
                3/28/2012
             | 
            
                -0.20 / -2.20%
             |             
            
                8.90
             |           
            
                9.10
             |               
            
                8.70
             |                           
            
                8.90
             | 
            
                8.90
             |                     
            
                5.79
             |                                 
            
                26,300
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/27/2012
             | 
            
                +0.20 / +2.25%
             |             
            
                8.80
             |           
            
                9.60
             |               
            
                8.70
             |                           
            
                9.10
             | 
            
                9.34
             |                     
            
                5.92
             |                                 
            
                124,600
             |            
            
                 
             |                                       
         
    
        
            | 
                3/26/2012
             | 
            
                -0.30 / -3.26%
             |             
            
                9.00
             |           
            
                9.20
             |               
            
                8.60
             |                           
            
                8.90
             | 
            
                9.00
             |                     
            
                5.79
             |                                 
            
                104,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/23/2012
             | 
            
                +0.40 / +4.55%
             |             
            
                8.70
             |           
            
                9.20
             |               
            
                8.70
             |                           
            
                9.20
             | 
            
                9.08
             |                     
            
                5.99
             |                                 
            
                110,600
             |            
            
                 
             |                                       
         
    
        
            | 
                3/22/2012
             | 
            
                +0.30 / +3.53%
             |             
            
                8.90
             |           
            
                8.90
             |               
            
                8.40
             |                           
            
                8.80
             | 
            
                8.73
             |                     
            
                5.73
             |                                 
            
                65,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/21/2012
             | 
            
                +0.10 / +1.19%
             |             
            
                8.10
             |           
            
                8.50
             |               
            
                8.10
             |                           
            
                8.50
             | 
            
                8.48
             |                     
            
                5.53
             |                                 
            
                37,800
             |            
            
                 
             |                                       
         
    
        
            | 
                3/20/2012
             | 
            
                0.00 / 0.00%
             |             
            
                8.40
             |           
            
                8.50
             |               
            
                8.10
             |                           
            
                8.40
             | 
            
                8.31
             |                     
            
                5.27
             |                                 
            
                122,500
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/19/2012
             | 
            
                -0.40 / -4.55%
             |             
            
                8.40
             |           
            
                8.70
             |               
            
                8.30
             |                           
            
                8.40
             | 
            
                8.39
             |                     
            
                5.27
             |                                 
            
                109,400
             |            
            
                 
             |                                       
         
    
        
            | 
                3/16/2012
             | 
            
                -0.20 / -2.22%
             |             
            
                9.00
             |           
            
                9.20
             |               
            
                8.60
             |                           
            
                8.80
             | 
            
                8.94
             |                     
            
                5.52
             |                                 
            
                92,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/15/2012
             | 
            
                +0.20 / +2.27%
             |             
            
                8.90
             |           
            
                9.50
             |               
            
                8.30
             |                           
            
                9.00
             | 
            
                8.62
             |                     
            
                5.65
             |                                 
            
                148,600
             |            
            
                 
             |                                       
         
    
        
            | 
                3/14/2012
             | 
            
                -0.50 / -5.38%
             |             
            
                9.20
             |           
            
                9.20
             |               
            
                8.80
             |                           
            
                8.80
             | 
            
                8.93
             |                     
            
                5.52
             |                                 
            
                82,000
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/13/2012
             | 
            
                -0.50 / -5.10%
             |             
            
                9.50
             |           
            
                9.80
             |               
            
                9.30
             |                           
            
                9.30
             | 
            
                9.35
             |                     
            
                5.84
             |                                 
            
                30,000
             |            
            
                 
             |                                       
         
    
        
            | 
                3/12/2012
             | 
            
                +0.30 / +3.16%
             |             
            
                10.10
             |           
            
                10.10
             |               
            
                9.60
             |                           
            
                9.80
             | 
            
                10.02
             |                     
            
                6.15
             |                                 
            
                226,400
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/9/2012
             | 
            
                +0.50 / +5.56%
             |             
            
                9.50
             |           
            
                9.50
             |               
            
                9.20
             |                           
            
                9.50
             | 
            
                9.50
             |                     
            
                5.96
             |                                 
            
                440,800
             |            
            
                 
             |                                       
         
    
        
            | 
                3/8/2012
             | 
            
                +0.50 / +5.88%
             |             
            
                8.50
             |           
            
                9.00
             |               
            
                8.50
             |                           
            
                9.00
             | 
            
                8.88
             |                     
            
                5.65
             |                                 
            
                159,200
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/7/2012
             | 
            
                0.00 / 0.00%
             |             
            
                8.80
             |           
            
                8.80
             |               
            
                8.40
             |                           
            
                8.50
             | 
            
                8.53
             |                     
            
                5.33
             |                                 
            
                40,600
             |            
            
                 
             |                                       
         
    
        
            | 
                3/6/2012
             | 
            
                -0.50 / -5.56%
             |             
            
                9.40
             |           
            
                9.40
             |               
            
                8.50
             |                           
            
                8.50
             | 
            
                8.90
             |                     
            
                5.33
             |                                 
            
                48,200
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/5/2012
             | 
            
                +0.20 / +2.27%
             |             
            
                8.60
             |           
            
                9.00
             |               
            
                8.50
             |                           
            
                9.00
             | 
            
                8.99
             |                     
            
                5.65
             |                                 
            
                124,900
             |            
            
                 
             |                                       
         
    
        
            | 
                3/2/2012
             | 
            
                +0.50 / +6.02%
             |             
            
                8.10
             |           
            
                8.80
             |               
            
                7.80
             |                           
            
                8.80
             | 
            
                8.55
             |                     
            
                5.52
             |                                 
            
                110,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/1/2012
             | 
            
                +0.20 / +2.47%
             |             
            
                8.40
             |           
            
                8.50
             |               
            
                8.10
             |                           
            
                8.30
             | 
            
                8.29
             |                     
            
                5.21
             |                                 
            
                18,700
             |            
            
                 
             |                                       
         
    
        
            | 
                2/29/2012
             | 
            
                -0.20 / -2.41%
             |             
            
                8.20
             |           
            
                8.30
             |               
            
                8.00
             |                           
            
                8.10
             | 
            
                8.05
             |                     
            
                5.08
             |                                 
            
                35,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/28/2012
             | 
            
                -0.80 / -8.79%
             |             
            
                9.00
             |           
            
                9.00
             |               
            
                8.30
             |                           
            
                8.30
             | 
            
                8.49
             |                     
            
                5.21
             |                                 
            
                40,100
             |            
            
                 
             |                                       
         
    
        
            | 
                2/27/2012
             | 
            
                +0.60 / +7.06%
             |             
            
                8.50
             |           
            
                9.20
             |               
            
                8.50
             |                           
            
                9.10
             | 
            
                8.88
             |                     
            
                5.71
             |                                 
            
                38,200
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/24/2012
             | 
            
                -0.20 / -2.30%
             |             
            
                8.80
             |           
            
                9.10
             |               
            
                8.20
             |                           
            
                8.50
             | 
            
                8.56
             |                     
            
                5.33
             |                                 
            
                25,500
             |            
            
                 
             |                                       
         
    
        
            | 
                2/23/2012
             | 
            
                +0.20 / +2.35%
             |             
            
                8.40
             |           
            
                8.70
             |               
            
                8.30
             |                           
            
                8.70
             | 
            
                8.63
             |                     
            
                5.46
             |                                 
            
                86,400
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/22/2012
             | 
            
                +0.20 / +2.41%
             |             
            
                8.30
             |           
            
                8.60
             |               
            
                8.00
             |                           
            
                8.50
             | 
            
                8.23
             |                     
            
                5.33
             |                                 
            
                52,800
             |            
            
                 
             |                                       
         
    
        
            | 
                2/21/2012
             | 
            
                -0.10 / -1.19%
             |             
            
                8.80
             |           
            
                8.80
             |               
            
                8.30
             |                           
            
                8.30
             | 
            
                8.60
             |                     
            
                5.21
             |                                 
            
                52,100
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/20/2012
             | 
            
                +0.40 / +5.00%
             |             
            
                8.10
             |           
            
                8.40
             |               
            
                8.00
             |                           
            
                8.40
             | 
            
                8.35
             |                     
            
                5.27
             |                                 
            
                50,900
             |            
            
                 
             |                                       
         
    
        
            | 
                2/17/2012
             | 
            
                +0.10 / +1.27%
             |             
            
                7.80
             |           
            
                8.10
             |               
            
                7.80
             |                           
            
                8.00
             | 
            
                7.88
             |                     
            
                5.02
             |                                 
            
                15,700
             |  
            
                 
             |                                                              
             
    
         
    
    
 |