|  | GROUP |  | 
   
  |  | 2001 $ million
 | 2000 $ million
 |  | 
  
  | REVENUES |  | 
   
  | Product sales | 590.6 | 472.1 |  | 
  
  | Interest and dividends | 5.9 | 10.0 |  | 
  
  | Other income - net | 11.9 | 8.5 |  | 
 
  |  | 
 |  | 
    
  |  | 608.4 | 490.6 |  | 
   
  |  | 
 |  | 
 
  |  | 
   
  | COSTS AND EXPENSES |  | 
  
  | Production costs | 502.2 | 399.1 |  | 
  
  | Depreciation and amortisation | 31.4 | 21.8 |  | 
  
  | Reversal of provision for rehabilitation cost | (6.8) | - |  | 
  
  | Corporate expenditure | 3.8 | 2.0 |  | 
   
  | Exploration expenditure | 3.5 | 2.5 |  | 
  
  | Marketing and new business expenditure | 4.9 | 1.9 |  | 
    
  | Gain on financial instruments | (7.9) | (8.6) |  | 
    
  | Profit on sale of other assets and listed investments (note 1.4) | 2.5 |  |  | 
    
  | Impairment of assets | 28.3 | - |  | 
      
  | Interest paid | 15.0 | 3.2 |  | 
      
  | Equity losses | - | 1.4 |  | 
      
  | Reversal of provision for former employee post-retirement benefits | (2.2) | (3.9) |  | 
   
  |  | 
 |  | 
    
  |  | 578.6 | 417.1 |  | 
   
  |  | 
 |  | 
  
  | Income before tax | 29.8 | 73.5 |  | 
  
  | Income and mining tax expense | (14.6) | (13.5) |  | 
     
  |  | 
 |  | 
   
  | Net income after tax and before minority interests | 15.2 | 60.0 |  | 
   
  | Minority interests | (0.4) | (2.9) |  | 
  
  |  | 
 |  | 
    
  | Net income before cumulative effect of change
in accounting policy | 14.8 | 57.1 |  | 
    
  |  | 
 |  | 
   
  |  | 
  
  | Basic earnings per share (US cents) before cumulative
effect of change in accounting principle | 14.5 | 68.2 |  | 
    
  | Diluted earnings per share (US cents) before cumulative
effect of change in accounting principle | 14.1 | 66.6 |  | 
    
  | Weighted average number of shares used in the
computation of basic earnings per share | 102,156,205 | 83,593,424 |  | 
    
  | Weighted average number of shares used in the
computation of diluted earnings per share | 105,504,325 | 85,590,876 |  |