| 
                 
                    Closing price on 5/30/2012
                 
             | 
            
                                
             | 
         
         
 
    
        
                      
                
                    | Open | 
                    12.00 | 
                 
                
                    | High | 
                    12.70 | 
                 
                
                    | Low | 
                    11.80 | 
                     
                
                    | Volume | 
                    42,800 | 
                                 
                
                    | Split-adjusted Price | 
                    7.94 | 
                 
             
            
            
                
             
         | 
        
            
            
             
                            
         | 
     
 
POT Historical Quote 
        
            
                | 
                    Date
                 | 
                
                    Change
                 |                 
                
                    Open
                 |          
                
                    High
                 |            
                
                    Low
                 |                                                 
                
                    Close
                 | 
                
                    Average
                 | 
                
                    Adjusted Close
                 |                                                 
                
                    Volume
                 |     
                
                     
                 |                                       
                             
    
        			
            | 
                5/30/2012
             | 
            
                +0.40 / +3.39%
             |             
            
                12.00
             |           
            
                12.70
             |               
            
                11.80
             |                           
            
                12.20
             | 
            
                12.04
             |                     
            
                7.94
             |                                 
            
                42,800
             |            
            
                 
             |                                       
         
    
        
            | 
                5/29/2012
             | 
            
                -0.20 / -1.67%
             |             
            
                11.90
             |           
            
                12.10
             |               
            
                11.50
             |                           
            
                11.80
             | 
            
                11.69
             |                     
            
                7.68
             |                                 
            
                90,300
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/28/2012
             | 
            
                -0.90 / -6.98%
             |             
            
                13.40
             |           
            
                13.40
             |               
            
                12.00
             |                           
            
                12.00
             | 
            
                12.36
             |                     
            
                7.81
             |                                 
            
                199,100
             |            
            
                 
             |                                       
         
    
        
            | 
                5/25/2012
             | 
            
                +0.60 / +4.88%
             |             
            
                12.50
             |           
            
                12.90
             |               
            
                12.50
             |                           
            
                12.90
             | 
            
                12.87
             |                     
            
                8.40
             |                                 
            
                65,409
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/24/2012
             | 
            
                -0.50 / -3.91%
             |             
            
                12.00
             |           
            
                12.70
             |               
            
                12.00
             |                           
            
                12.30
             | 
            
                12.11
             |                     
            
                8.01
             |                                 
            
                140,204
             |            
            
                 
             |                                       
         
    
        
            | 
                5/23/2012
             | 
            
                -1.00 / -7.25%
             |             
            
                13.30
             |           
            
                13.80
             |               
            
                12.80
             |                           
            
                12.80
             | 
            
                12.98
             |                     
            
                8.33
             |                                 
            
                160,400
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/22/2012
             | 
            
                +0.90 / +6.98%
             |             
            
                12.70
             |           
            
                13.80
             |               
            
                12.70
             |                           
            
                13.80
             | 
            
                13.59
             |                     
            
                8.98
             |                                 
            
                251,924
             |            
            
                 
             |                                       
         
    
        
            | 
                5/21/2012
             | 
            
                +0.80 / +6.61%
             |             
            
                12.40
             |           
            
                12.90
             |               
            
                12.40
             |                           
            
                12.90
             | 
            
                12.78
             |                     
            
                8.40
             |                                 
            
                115,540
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/18/2012
             | 
            
                -1.00 / -7.63%
             |             
            
                12.80
             |           
            
                12.80
             |               
            
                12.10
             |                           
            
                12.10
             | 
            
                12.14
             |                     
            
                7.88
             |                                 
            
                331,800
             |            
            
                 
             |                                       
         
    
        
            | 
                5/17/2012
             | 
            
                -0.50 / -3.68%
             |             
            
                13.50
             |           
            
                14.00
             |               
            
                13.00
             |                           
            
                13.10
             | 
            
                13.50
             |                     
            
                8.53
             |                                 
            
                101,300
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/16/2012
             | 
            
                -0.60 / -4.23%
             |             
            
                14.40
             |           
            
                14.40
             |               
            
                13.30
             |                           
            
                13.60
             | 
            
                13.42
             |                     
            
                8.85
             |                                 
            
                205,200
             |            
            
                 
             |                                       
         
    
        
            | 
                5/15/2012
             | 
            
                -1.00 / -6.58%
             |             
            
                15.30
             |           
            
                15.30
             |               
            
                14.20
             |                           
            
                14.20
             | 
            
                14.41
             |                     
            
                9.24
             |                                 
            
                204,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/14/2012
             | 
            
                +0.50 / +3.40%
             |             
            
                14.70
             |           
            
                15.70
             |               
            
                14.50
             |                           
            
                15.20
             | 
            
                15.43
             |                     
            
                9.90
             |                                 
            
                521,744
             |            
            
                 
             |                                       
         
    
        
            | 
                5/11/2012
             | 
            
                -0.10 / -0.68%
             |             
            
                14.00
             |           
            
                15.00
             |               
            
                14.00
             |                           
            
                14.70
             | 
            
                14.55
             |                     
            
                9.57
             |                                 
            
                213,740
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/10/2012
             | 
            
                -1.10 / -6.92%
             |             
            
                16.70
             |           
            
                16.70
             |               
            
                14.80
             |                           
            
                14.80
             | 
            
                15.10
             |                     
            
                9.64
             |                                 
            
                298,516
             |            
            
                 
             |                                       
         
    
        
            | 
                5/9/2012
             | 
            
                +1.00 / +6.71%
             |             
            
                15.80
             |           
            
                15.90
             |               
            
                14.90
             |                           
            
                15.90
             | 
            
                15.75
             |                     
            
                10.35
             |                                 
            
                608,200
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/8/2012
             | 
            
                +0.90 / +6.43%
             |             
            
                14.90
             |           
            
                14.90
             |               
            
                14.50
             |                           
            
                14.90
             | 
            
                14.90
             |                     
            
                9.70
             |                                 
            
                1,050,769
             |            
            
                 
             |                                       
         
    
        
            | 
                5/7/2012
             | 
            
                +0.90 / +6.87%
             |             
            
                14.00
             |           
            
                14.00
             |               
            
                14.00
             |                           
            
                14.00
             | 
            
                14.00
             |                     
            
                9.11
             |                                 
            
                128,656
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/4/2012
             | 
            
                +0.80 / +6.50%
             |             
            
                13.10
             |           
            
                13.10
             |               
            
                13.10
             |                           
            
                13.10
             | 
            
                13.10
             |                     
            
                8.53
             |                                 
            
                101,864
             |            
            
                 
             |                                       
         
    
        
            | 
                5/3/2012
             | 
            
                +0.80 / +6.96%
             |             
            
                12.30
             |           
            
                12.30
             |               
            
                12.30
             |                           
            
                12.30
             | 
            
                12.30
             |                     
            
                8.01
             |                                 
            
                63,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                5/2/2012
             | 
            
                +0.70 / +6.48%
             |             
            
                11.50
             |           
            
                11.50
             |               
            
                11.50
             |                           
            
                11.50
             | 
            
                11.50
             |                     
            
                7.49
             |                                 
            
                6,000
             |            
            
                 
             |                                       
         
    
        
            | 
                4/27/2012
             | 
            
                +0.70 / +6.93%
             |             
            
                10.80
             |           
            
                10.80
             |               
            
                10.80
             |                           
            
                10.80
             | 
            
                10.80
             |                     
            
                7.03
             |                                 
            
                47,648
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/26/2012
             | 
            
                +0.60 / +6.32%
             |             
            
                10.00
             |           
            
                10.10
             |               
            
                9.50
             |                           
            
                10.10
             | 
            
                9.99
             |                     
            
                6.58
             |                                 
            
                213,500
             |            
            
                 
             |                                       
         
    
        
            | 
                4/25/2012
             | 
            
                +0.70 / +7.95%
             |             
            
                9.10
             |           
            
                9.50
             |               
            
                9.10
             |                           
            
                9.50
             | 
            
                9.49
             |                     
            
                6.18
             |                                 
            
                176,100
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/24/2012
             | 
            
                0.00 / 0.00%
             |             
            
                8.50
             |           
            
                9.00
             |               
            
                8.50
             |                           
            
                8.80
             | 
            
                8.79
             |                     
            
                5.73
             |                                 
            
                29,400
             |            
            
                 
             |                                       
         
    
        
            | 
                4/23/2012
             | 
            
                0.00 / 0.00%
             |             
            
                8.90
             |           
            
                8.90
             |               
            
                8.60
             |                           
            
                8.80
             | 
            
                8.65
             |                     
            
                5.73
             |                                 
            
                21,000
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/20/2012
             | 
            
                0.00 / 0.00%
             |             
            
                8.80
             |           
            
                8.90
             |               
            
                8.70
             |                           
            
                8.80
             | 
            
                8.80
             |                     
            
                5.73
             |                                 
            
                10,980
             |            
            
                 
             |                                       
         
    
        
            | 
                4/19/2012
             | 
            
                -0.20 / -2.22%
             |             
            
                8.90
             |           
            
                8.90
             |               
            
                8.60
             |                           
            
                8.80
             | 
            
                8.72
             |                     
            
                5.73
             |                                 
            
                31,280
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/18/2012
             | 
            
                -0.10 / -1.10%
             |             
            
                9.50
             |           
            
                9.50
             |               
            
                8.90
             |                           
            
                9.00
             | 
            
                9.08
             |                     
            
                5.86
             |                                 
            
                53,000
             |            
            
                 
             |                                       
         
    
        
            | 
                4/17/2012
             | 
            
                +0.10 / +1.11%
             |             
            
                9.40
             |           
            
                9.60
             |               
            
                9.10
             |                           
            
                9.10
             | 
            
                9.35
             |                     
            
                5.92
             |                                 
            
                96,820
             |  
            
                 
             |                                                              
             
    
         
    
    
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