| 
                 
                    Closing price on 4/25/2012
                 
             | 
            
                                
             | 
         
         
 
    
        
                      
                
                    | Open | 
                    7.30 | 
                 
                
                    | High | 
                    7.70 | 
                 
                
                    | Low | 
                    7.20 | 
                     
                
                    | Volume | 
                    508,400 | 
                                 
                
                    | Split-adjusted Price | 
                    6.61 | 
                 
             
            
            
                
             
         | 
        
            
            
             
                            
         | 
     
 
IVS Historical Quote 
        
            
                | 
                    Date
                 | 
                
                    Change
                 |                 
                
                    Open
                 |          
                
                    High
                 |            
                
                    Low
                 |                                                 
                
                    Close
                 | 
                
                    Average
                 | 
                
                    Adjusted Close
                 |                                                 
                
                    Volume
                 |     
                
                     
                 |                                       
                             
    
        			
            | 
                4/25/2012
             | 
            
                +0.50 / +6.94%
             |             
            
                7.30
             |           
            
                7.70
             |               
            
                7.20
             |                           
            
                7.70
             | 
            
                7.61
             |                     
            
                6.61
             |                                 
            
                508,400
             |            
            
                 
             |                                       
         
    
        
            | 
                4/24/2012
             | 
            
                +0.40 / +5.88%
             |             
            
                6.90
             |           
            
                7.20
             |               
            
                6.90
             |                           
            
                7.20
             | 
            
                7.14
             |                     
            
                6.18
             |                                 
            
                688,000
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/23/2012
             | 
            
                +0.40 / +6.25%
             |             
            
                6.70
             |           
            
                6.80
             |               
            
                6.50
             |                           
            
                6.80
             | 
            
                6.78
             |                     
            
                5.84
             |                                 
            
                526,800
             |            
            
                 
             |                                       
         
    
        
            | 
                4/20/2012
             | 
            
                0.00 / 0.00%
             |             
            
                6.40
             |           
            
                6.40
             |               
            
                6.20
             |                           
            
                6.40
             | 
            
                6.39
             |                     
            
                5.50
             |                                 
            
                229,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/19/2012
             | 
            
                -0.30 / -4.48%
             |             
            
                6.60
             |           
            
                6.60
             |               
            
                6.30
             |                           
            
                6.40
             | 
            
                6.41
             |                     
            
                5.50
             |                                 
            
                215,600
             |            
            
                 
             |                                       
         
    
        
            | 
                4/18/2012
             | 
            
                0.00 / 0.00%
             |             
            
                6.80
             |           
            
                6.80
             |               
            
                6.40
             |                           
            
                6.70
             | 
            
                6.66
             |                     
            
                5.75
             |                                 
            
                126,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/17/2012
             | 
            
                -0.20 / -2.90%
             |             
            
                6.90
             |           
            
                7.00
             |               
            
                6.60
             |                           
            
                6.70
             | 
            
                6.76
             |                     
            
                5.75
             |                                 
            
                238,200
             |            
            
                 
             |                                       
         
    
        
            | 
                4/16/2012
             | 
            
                +0.10 / +1.47%
             |             
            
                6.80
             |           
            
                7.00
             |               
            
                6.80
             |                           
            
                6.90
             | 
            
                6.87
             |                     
            
                5.93
             |                                 
            
                220,900
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/13/2012
             | 
            
                0.00 / 0.00%
             |             
            
                6.80
             |           
            
                7.10
             |               
            
                6.60
             |                           
            
                6.80
             | 
            
                6.93
             |                     
            
                5.84
             |                                 
            
                198,700
             |            
            
                 
             |                                       
         
    
        
            | 
                4/12/2012
             | 
            
                +0.20 / +3.03%
             |             
            
                6.70
             |           
            
                7.00
             |               
            
                6.70
             |                           
            
                6.80
             | 
            
                6.87
             |                     
            
                5.84
             |                                 
            
                233,300
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/11/2012
             | 
            
                +0.40 / +6.45%
             |             
            
                6.30
             |           
            
                6.60
             |               
            
                6.20
             |                           
            
                6.60
             | 
            
                6.56
             |                     
            
                5.67
             |                                 
            
                431,600
             |            
            
                 
             |                                       
         
    
        
            | 
                4/10/2012
             | 
            
                -0.10 / -1.59%
             |             
            
                6.20
             |           
            
                6.30
             |               
            
                6.10
             |                           
            
                6.20
             | 
            
                6.15
             |                     
            
                5.32
             |                                 
            
                158,400
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/9/2012
             | 
            
                +0.10 / +1.61%
             |             
            
                6.20
             |           
            
                6.30
             |               
            
                6.10
             |                           
            
                6.30
             | 
            
                6.19
             |                     
            
                5.41
             |                                 
            
                125,600
             |            
            
                 
             |                                       
         
    
        
            | 
                4/6/2012
             | 
            
                0.00 / 0.00%
             |             
            
                6.20
             |           
            
                6.30
             |               
            
                6.10
             |                           
            
                6.20
             | 
            
                6.28
             |                     
            
                5.32
             |                                 
            
                121,200
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/5/2012
             | 
            
                +0.30 / +5.08%
             |             
            
                6.00
             |           
            
                6.20
             |               
            
                5.90
             |                           
            
                6.20
             | 
            
                6.08
             |                     
            
                5.32
             |                                 
            
                142,300
             |            
            
                 
             |                                       
         
    
        
            | 
                4/4/2012
             | 
            
                -0.20 / -3.28%
             |             
            
                6.10
             |           
            
                6.20
             |               
            
                5.90
             |                           
            
                5.90
             | 
            
                6.05
             |                     
            
                5.07
             |                                 
            
                243,000
             |  
            
                 
             |                                                              
             
    
        			
            | 
                4/3/2012
             | 
            
                +0.30 / +5.17%
             |             
            
                5.90
             |           
            
                6.20
             |               
            
                5.80
             |                           
            
                6.10
             | 
            
                6.09
             |                     
            
                5.24
             |                                 
            
                273,400
             |            
            
                 
             |                                       
         
    
        
            | 
                3/30/2012
             | 
            
                -0.10 / -1.69%
             |             
            
                5.90
             |           
            
                6.00
             |               
            
                5.60
             |                           
            
                5.80
             | 
            
                5.84
             |                     
            
                4.98
             |                                 
            
                183,200
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/29/2012
             | 
            
                -0.30 / -4.84%
             |             
            
                6.20
             |           
            
                6.20
             |               
            
                5.80
             |                           
            
                5.90
             | 
            
                6.06
             |                     
            
                5.07
             |                                 
            
                160,200
             |            
            
                 
             |                                       
         
    
        
            | 
                3/28/2012
             | 
            
                -0.40 / -6.06%
             |             
            
                6.30
             |           
            
                6.40
             |               
            
                6.20
             |                           
            
                6.20
             | 
            
                6.25
             |                     
            
                5.32
             |                                 
            
                184,500
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/27/2012
             | 
            
                -0.40 / -5.71%
             |             
            
                7.00
             |           
            
                7.10
             |               
            
                6.60
             |                           
            
                6.60
             | 
            
                6.69
             |                     
            
                5.67
             |                                 
            
                218,500
             |            
            
                 
             |                                       
         
    
        
            | 
                3/26/2012
             | 
            
                +0.10 / +1.45%
             |             
            
                7.10
             |           
            
                7.30
             |               
            
                6.70
             |                           
            
                7.00
             | 
            
                6.96
             |                     
            
                6.01
             |                                 
            
                183,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/23/2012
             | 
            
                0.00 / 0.00%
             |             
            
                7.20
             |           
            
                7.20
             |               
            
                6.80
             |                           
            
                6.90
             | 
            
                7.11
             |                     
            
                5.93
             |                                 
            
                375,200
             |            
            
                 
             |                                       
         
    
        
            | 
                3/22/2012
             | 
            
                -0.20 / -2.82%
             |             
            
                7.30
             |           
            
                7.50
             |               
            
                6.80
             |                           
            
                6.90
             | 
            
                7.15
             |                     
            
                5.93
             |                                 
            
                395,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/21/2012
             | 
            
                0.00 / 0.00%
             |             
            
                7.10
             |           
            
                7.50
             |               
            
                7.10
             |                           
            
                7.10
             | 
            
                7.28
             |                     
            
                6.10
             |                                 
            
                717,400
             |            
            
                 
             |                                       
         
    
        
            | 
                3/20/2012
             | 
            
                0.00 / 0.00%
             |             
            
                6.70
             |           
            
                7.30
             |               
            
                6.70
             |                           
            
                7.10
             | 
            
                7.14
             |                     
            
                6.10
             |                                 
            
                474,000
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/19/2012
             | 
            
                +0.10 / +1.43%
             |             
            
                7.00
             |           
            
                7.30
             |               
            
                6.90
             |                           
            
                7.10
             | 
            
                7.19
             |                     
            
                6.10
             |                                 
            
                267,200
             |            
            
                 
             |                                       
         
    
        
            | 
                3/16/2012
             | 
            
                +0.10 / +1.45%
             |             
            
                6.70
             |           
            
                7.00
             |               
            
                6.70
             |                           
            
                7.00
             | 
            
                6.96
             |                     
            
                6.01
             |                                 
            
                1,173,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                3/15/2012
             | 
            
                +0.50 / +7.81%
             |             
            
                6.60
             |           
            
                7.00
             |               
            
                6.20
             |                           
            
                6.90
             | 
            
                6.57
             |                     
            
                5.93
             |                                 
            
                275,800
             |            
            
                 
             |                                       
         
    
        
            | 
                3/14/2012
             | 
            
                -0.40 / -5.88%
             |             
            
                6.60
             |           
            
                6.80
             |               
            
                6.20
             |                           
            
                6.40
             | 
            
                6.63
             |                     
            
                5.50
             |                                 
            
                405,200
             |  
            
                 
             |                                                              
             
    
         
    
    
 |