| 
                 
                    Closing price on 2/21/2012
                 
             | 
            
                                
             | 
         
         
 
    
        
                      
                
                    | Open | 
                    8.80 | 
                 
                
                    | High | 
                    8.80 | 
                 
                
                    | Low | 
                    8.30 | 
                     
                
                    | Volume | 
                    52,100 | 
                                 
                
                    | Split-adjusted Price | 
                    5.21 | 
                 
             
            
            
                
             
         | 
        
            
            
             
                            
         | 
     
 
POT Historical Quote 
        
            
                | 
                    Date
                 | 
                
                    Change
                 |                 
                
                    Open
                 |          
                
                    High
                 |            
                
                    Low
                 |                                                 
                
                    Close
                 | 
                
                    Average
                 | 
                
                    Adjusted Close
                 |                                                 
                
                    Volume
                 |     
                
                     
                 |                                       
                             
    
        			
            | 
                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
             |            
            
                 
             |                                       
         
    
        
            | 
                2/16/2012
             | 
            
                +0.10 / +1.28%
             |             
            
                7.90
             |           
            
                7.90
             |               
            
                7.90
             |                           
            
                7.90
             | 
            
                7.90
             |                     
            
                4.96
             |                                 
            
                1,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/15/2012
             | 
            
                -0.30 / -3.70%
             |             
            
                7.90
             |           
            
                8.20
             |               
            
                7.60
             |                           
            
                7.80
             | 
            
                7.80
             |                     
            
                4.89
             |                                 
            
                14,200
             |            
            
                 
             |                                       
         
    
        
            | 
                2/14/2012
             | 
            
                0.00 / 0.00%
             |             
            
                8.10
             |           
            
                8.20
             |               
            
                7.80
             |                           
            
                8.10
             | 
            
                8.06
             |                     
            
                5.08
             |                                 
            
                9,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/13/2012
             | 
            
                +0.10 / +1.25%
             |             
            
                8.00
             |           
            
                8.30
             |               
            
                7.90
             |                           
            
                8.10
             | 
            
                8.12
             |                     
            
                5.08
             |                                 
            
                10,700
             |            
            
                 
             |                                       
         
    
        
            | 
                2/10/2012
             | 
            
                -0.40 / -4.76%
             |             
            
                8.30
             |           
            
                8.40
             |               
            
                8.00
             |                           
            
                8.00
             | 
            
                8.20
             |                     
            
                5.02
             |                                 
            
                43,000
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/9/2012
             | 
            
                +0.40 / +5.00%
             |             
            
                8.20
             |           
            
                8.40
             |               
            
                8.20
             |                           
            
                8.40
             | 
            
                8.39
             |                     
            
                5.27
             |                                 
            
                54,400
             |            
            
                 
             |                                       
         
    
        
            | 
                2/8/2012
             | 
            
                +0.30 / +3.90%
             |             
            
                7.80
             |           
            
                8.00
             |               
            
                7.70
             |                           
            
                8.00
             | 
            
                7.92
             |                     
            
                5.02
             |                                 
            
                63,900
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/7/2012
             | 
            
                +0.40 / +5.48%
             |             
            
                7.90
             |           
            
                7.90
             |               
            
                7.40
             |                           
            
                7.70
             | 
            
                7.52
             |                     
            
                4.83
             |                                 
            
                10,300
             |            
            
                 
             |                                       
         
    
        
            | 
                2/6/2012
             | 
            
                -0.20 / -2.67%
             |             
            
                7.40
             |           
            
                7.40
             |               
            
                7.30
             |                           
            
                7.30
             | 
            
                7.35
             |                     
            
                4.58
             |                                 
            
                20,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/3/2012
             | 
            
                -0.20 / -2.60%
             |             
            
                7.70
             |           
            
                7.70
             |               
            
                7.20
             |                           
            
                7.50
             | 
            
                7.44
             |                     
            
                4.71
             |                                 
            
                29,400
             |            
            
                 
             |                                       
         
    
        
            | 
                2/2/2012
             | 
            
                +0.20 / +2.67%
             |             
            
                7.80
             |           
            
                7.90
             |               
            
                7.60
             |                           
            
                7.70
             | 
            
                7.73
             |                     
            
                4.83
             |                                 
            
                33,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                2/1/2012
             | 
            
                -0.10 / -1.32%
             |             
            
                7.80
             |           
            
                7.80
             |               
            
                7.50
             |                           
            
                7.50
             | 
            
                7.54
             |                     
            
                4.71
             |                                 
            
                800
             |            
            
                 
             |                                       
         
    
        
            | 
                1/31/2012
             | 
            
                +0.10 / +1.33%
             |             
            
                7.90
             |           
            
                7.90
             |               
            
                7.50
             |                           
            
                7.60
             | 
            
                7.55
             |                     
            
                4.77
             |                                 
            
                33,500
             |  
            
                 
             |                                                              
             
    
        			
            | 
                1/30/2012
             | 
            
                0.00 / 0.00%
             |             
            
                7.50
             |           
            
                7.50
             |               
            
                7.50
             |                           
            
                7.50
             | 
            
                7.50
             |                     
            
                4.71
             |                                 
            
                2,200
             |            
            
                 
             |                                       
         
    
        
            | 
                1/20/2012
             | 
            
                0.00 / 0.00%
             |             
            
                7.50
             |           
            
                7.50
             |               
            
                7.50
             |                           
            
                7.50
             | 
            
                7.50
             |                     
            
                4.71
             |                                 
            
                200
             |  
            
                 
             |                                                              
             
    
        			
            | 
                1/19/2012
             | 
            
                +0.50 / +7.14%
             |             
            
                7.30
             |           
            
                7.50
             |               
            
                7.30
             |                           
            
                7.50
             | 
            
                7.45
             |                     
            
                4.71
             |                                 
            
                11,100
             |            
            
                 
             |                                       
         
    
        
            | 
                1/18/2012
             | 
            
                -0.30 / -4.11%
             |             
            
                7.30
             |           
            
                7.40
             |               
            
                7.00
             |                           
            
                7.00
             | 
            
                7.12
             |                     
            
                4.39
             |                                 
            
                10,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                1/17/2012
             | 
            
                +0.40 / +5.80%
             |             
            
                7.30
             |           
            
                7.30
             |               
            
                7.00
             |                           
            
                7.30
             | 
            
                7.15
             |                     
            
                4.58
             |                                 
            
                2,300
             |            
            
                 
             |                                       
         
    
        
            | 
                1/16/2012
             | 
            
                -0.50 / -6.76%
             |             
            
                7.40
             |           
            
                7.40
             |               
            
                6.90
             |                           
            
                6.90
             | 
            
                7.13
             |                     
            
                4.33
             |                                 
            
                6,900
             |  
            
                 
             |                                                              
             
    
        			
            | 
                1/13/2012
             | 
            
                +0.20 / +2.78%
             |             
            
                7.30
             |           
            
                7.50
             |               
            
                7.20
             |                           
            
                7.40
             | 
            
                7.32
             |                     
            
                4.64
             |                                 
            
                8,700
             |            
            
                 
             |                                       
         
    
        
            | 
                1/12/2012
             | 
            
                +0.10 / +1.41%
             |             
            
                7.00
             |           
            
                7.40
             |               
            
                7.00
             |                           
            
                7.20
             | 
            
                7.28
             |                     
            
                4.52
             |                                 
            
                3,400
             |  
            
                 
             |                                                              
             
    
        			
            | 
                1/11/2012
             | 
            
                -0.50 / -6.58%
             |             
            
                7.80
             |           
            
                7.80
             |               
            
                7.00
             |                           
            
                7.10
             | 
            
                7.24
             |                     
            
                4.46
             |                                 
            
                15,900
             |            
            
                 
             |                                       
         
    
        
            | 
                1/10/2012
             | 
            
                -0.10 / -1.30%
             |             
            
                7.30
             |           
            
                7.60
             |               
            
                7.20
             |                           
            
                7.60
             | 
            
                7.53
             |                     
            
                4.77
             |                                 
            
                2,000
             |  
            
                 
             |                                                              
             
    
        			
            | 
                1/9/2012
             | 
            
                +0.10 / +1.32%
             |             
            
                8.00
             |           
            
                8.10
             |               
            
                7.60
             |                           
            
                7.70
             | 
            
                7.74
             |                     
            
                4.83
             |                                 
            
                2,500
             |            
            
                 
             |                                       
         
    
        
            | 
                1/6/2012
             | 
            
                +0.20 / +2.70%
             |             
            
                7.60
             |           
            
                7.60
             |               
            
                7.60
             |                           
            
                7.60
             | 
            
                7.60
             |                     
            
                4.77
             |                                 
            
                0
             |  
            
                 
             |                                                              
             
    
        			
            | 
                1/5/2012
             | 
            
                -0.20 / -2.63%
             |             
            
                7.60
             |           
            
                7.60
             |               
            
                7.40
             |                           
            
                7.40
             | 
            
                7.57
             |                     
            
                4.64
             |                                 
            
                600
             |            
            
                 
             |                                       
         
    
        
            | 
                1/4/2012
             | 
            
                +0.20 / +2.70%
             |             
            
                7.70
             |           
            
                7.70
             |               
            
                7.60
             |                           
            
                7.60
             | 
            
                7.64
             |                     
            
                4.77
             |                                 
            
                1,800
             |  
            
                 
             |                                                              
             
    
         
    
    
 |