| 
                 
                    Closing price on 7/13/2018
                 
             | 
            
                                
             | 
         
         
 
    
        
                      
                
                    | Open | 
                    3.60 | 
                 
                
                    | High | 
                    3.80 | 
                 
                
                    | Low | 
                    3.60 | 
                     
                
                    | Volume | 
                    981,700 | 
                                 
                
                    | Split-adjusted Price | 
                    2.59 | 
                 
             
            
            
                
             
         | 
        
            
            
             
                            
         | 
     
 
MST Historical Quote 
        
            
                | 
                    Date
                 | 
                
                    Change
                 |                 
                
                    Open
                 |          
                
                    High
                 |            
                
                    Low
                 |                                                 
                
                    Close
                 | 
                
                    Average
                 | 
                
                    Adjusted Close
                 |                                                 
                
                    Volume
                 |     
                
                     
                 |                                       
                             
    
        			
            | 
                7/13/2018
             | 
            
                +0.20 / +5.56%
             |             
            
                3.60
             |           
            
                3.80
             |               
            
                3.60
             |                           
            
                3.80
             | 
            
                3.68
             |                     
            
                2.59
             |                                 
            
                981,700
             |            
            
                 
             |                                       
         
    
        
            | 
                7/12/2018
             | 
            
                -0.10 / -2.70%
             |             
            
                3.70
             |           
            
                3.80
             |               
            
                3.60
             |                           
            
                3.60
             | 
            
                3.71
             |                     
            
                2.46
             |                                 
            
                587,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                7/11/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.70
             |           
            
                3.70
             |               
            
                3.60
             |                           
            
                3.70
             | 
            
                3.63
             |                     
            
                2.52
             |                                 
            
                57,900
             |            
            
                 
             |                                       
         
    
        
            | 
                7/10/2018
             | 
            
                -0.10 / -2.63%
             |             
            
                3.60
             |           
            
                3.80
             |               
            
                3.60
             |                           
            
                3.70
             | 
            
                3.71
             |                     
            
                2.52
             |                                 
            
                685,500
             |  
            
                 
             |                                                              
             
    
        			
            | 
                7/9/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.80
             |           
            
                3.80
             |               
            
                3.60
             |                           
            
                3.80
             | 
            
                3.67
             |                     
            
                2.59
             |                                 
            
                394,400
             |            
            
                 
             |                                       
         
    
        
            | 
                7/6/2018
             | 
            
                +0.10 / +2.70%
             |             
            
                3.60
             |           
            
                3.80
             |               
            
                3.60
             |                           
            
                3.80
             | 
            
                3.73
             |                     
            
                2.59
             |                                 
            
                563,100
             |  
            
                 
             |                                                              
             
    
        			
            | 
                7/5/2018
             | 
            
                -0.10 / -2.63%
             |             
            
                3.70
             |           
            
                3.80
             |               
            
                3.50
             |                           
            
                3.70
             | 
            
                3.61
             |                     
            
                2.52
             |                                 
            
                151,900
             |            
            
                 
             |                                       
         
    
        
            | 
                7/4/2018
             | 
            
                +0.30 / +8.57%
             |             
            
                3.50
             |           
            
                3.80
             |               
            
                3.50
             |                           
            
                3.80
             | 
            
                3.67
             |                     
            
                2.59
             |                                 
            
                192,800
             |  
            
                 
             |                                                              
             
    
        			
            | 
                7/3/2018
             | 
            
                -0.20 / -5.41%
             |             
            
                3.70
             |           
            
                3.80
             |               
            
                3.50
             |                           
            
                3.50
             | 
            
                3.60
             |                     
            
                2.39
             |                                 
            
                362,500
             |            
            
                 
             |                                       
         
    
        
            | 
                7/2/2018
             | 
            
                -0.20 / -5.13%
             |             
            
                3.80
             |           
            
                3.90
             |               
            
                3.70
             |                           
            
                3.70
             | 
            
                3.80
             |                     
            
                2.52
             |                                 
            
                250,600
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/29/2018
             | 
            
                +0.20 / +5.41%
             |             
            
                3.70
             |           
            
                3.90
             |               
            
                3.60
             |                           
            
                3.90
             | 
            
                3.79
             |                     
            
                2.66
             |                                 
            
                401,800
             |            
            
                 
             |                                       
         
    
        
            | 
                6/28/2018
             | 
            
                -0.30 / -7.50%
             |             
            
                4.00
             |           
            
                4.00
             |               
            
                3.70
             |                           
            
                3.70
             | 
            
                3.86
             |                     
            
                2.52
             |                                 
            
                388,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/27/2018
             | 
            
                +0.20 / +5.26%
             |             
            
                3.70
             |           
            
                4.00
             |               
            
                3.60
             |                           
            
                4.00
             | 
            
                3.85
             |                     
            
                2.73
             |                                 
            
                667,400
             |            
            
                 
             |                                       
         
    
        
            | 
                6/26/2018
             | 
            
                -0.10 / -2.56%
             |             
            
                3.90
             |           
            
                4.00
             |               
            
                3.70
             |                           
            
                3.80
             | 
            
                3.84
             |                     
            
                2.59
             |                                 
            
                400,900
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/25/2018
             | 
            
                +0.20 / +5.41%
             |             
            
                3.70
             |           
            
                3.90
             |               
            
                3.60
             |                           
            
                3.90
             | 
            
                3.80
             |                     
            
                2.66
             |                                 
            
                796,400
             |            
            
                 
             |                                       
         
    
        
            | 
                6/22/2018
             | 
            
                +0.20 / +5.71%
             |             
            
                3.50
             |           
            
                3.70
             |               
            
                3.50
             |                           
            
                3.70
             | 
            
                3.57
             |                     
            
                2.52
             |                                 
            
                520,300
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/21/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.50
             |           
            
                3.60
             |               
            
                3.40
             |                           
            
                3.50
             | 
            
                3.48
             |                     
            
                2.39
             |                                 
            
                452,009
             |            
            
                 
             |                                       
         
    
        
            | 
                6/20/2018
             | 
            
                -0.10 / -2.78%
             |             
            
                3.60
             |           
            
                3.80
             |               
            
                3.40
             |                           
            
                3.50
             | 
            
                3.56
             |                     
            
                2.39
             |                                 
            
                329,100
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/19/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.50
             |           
            
                3.60
             |               
            
                3.30
             |                           
            
                3.60
             | 
            
                3.50
             |                     
            
                2.46
             |                                 
            
                721,700
             |            
            
                 
             |                                       
         
    
        
            | 
                6/18/2018
             | 
            
                +0.10 / +2.86%
             |             
            
                3.60
             |           
            
                3.60
             |               
            
                3.50
             |                           
            
                3.60
             | 
            
                3.59
             |                     
            
                2.46
             |                                 
            
                157,800
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/15/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.50
             |           
            
                3.70
             |               
            
                3.50
             |                           
            
                3.50
             | 
            
                3.59
             |                     
            
                2.39
             |                                 
            
                408,200
             |            
            
                 
             |                                       
         
    
        
            | 
                6/14/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.50
             |           
            
                3.70
             |               
            
                3.40
             |                           
            
                3.50
             | 
            
                3.57
             |                     
            
                2.39
             |                                 
            
                616,500
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/13/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.50
             |           
            
                3.80
             |               
            
                3.50
             |                           
            
                3.50
             | 
            
                3.56
             |                     
            
                2.39
             |                                 
            
                636,600
             |            
            
                 
             |                                       
         
    
        
            | 
                6/12/2018
             | 
            
                -0.10 / -2.78%
             |             
            
                3.60
             |           
            
                3.60
             |               
            
                3.40
             |                           
            
                3.50
             | 
            
                3.50
             |                     
            
                2.39
             |                                 
            
                727,500
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/11/2018
             | 
            
                -0.30 / -7.69%
             |             
            
                3.90
             |           
            
                4.00
             |               
            
                3.60
             |                           
            
                3.60
             | 
            
                3.71
             |                     
            
                2.46
             |                                 
            
                412,800
             |            
            
                 
             |                                       
         
    
        
            | 
                6/8/2018
             | 
            
                0.00 / 0.00%
             |             
            
                3.90
             |           
            
                3.90
             |               
            
                3.70
             |                           
            
                3.90
             | 
            
                3.77
             |                     
            
                2.66
             |                                 
            
                769,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/7/2018
             | 
            
                0.00 / 0.00%
             |             
            
                4.20
             |           
            
                4.20
             |               
            
                3.90
             |                           
            
                3.90
             | 
            
                4.03
             |                     
            
                2.66
             |                                 
            
                1,212,700
             |            
            
                 
             |                                       
         
    
        
            | 
                6/6/2018
             | 
            
                +0.30 / +8.33%
             |             
            
                3.60
             |           
            
                3.90
             |               
            
                3.60
             |                           
            
                3.90
             | 
            
                3.81
             |                     
            
                2.66
             |                                 
            
                815,700
             |  
            
                 
             |                                                              
             
    
        			
            | 
                6/5/2018
             | 
            
                +0.10 / +2.86%
             |             
            
                3.60
             |           
            
                3.60
             |               
            
                3.50
             |                           
            
                3.60
             | 
            
                3.57
             |                     
            
                2.46
             |                                 
            
                1,361,400
             |            
            
                 
             |                                       
         
    
        
            | 
                6/4/2018
             | 
            
                +0.10 / +2.94%
             |             
            
                3.40
             |           
            
                3.60
             |               
            
                3.40
             |                           
            
                3.50
             | 
            
                3.48
             |                     
            
                2.39
             |                                 
            
                469,000
             |  
            
                 
             |                                                              
             
    
         
    
    
 |