25 Authorised and issued share capital
 
 
  2006 
Million 
2005 
Million 
2006 
£m 
2005 
£m 
Authorised        
Ordinary shares of 2p each 1,000.0  1,000.0  20.0  20.0 
Allotted, called up and fully paid        
Ordinary shares of 2p each        
At 1 January 671.0  670.9  13.4  13.4 
Shares repurchased (52.9) (5.0) (1.1) (0.1)
Issued on exercise of share options 16.4  5.0  0.4  0.1 
Issued on acquisition of subsidiary undertaking 0.1 
Treasury shares cancelled (16.9) (0.4)
At 31 December 617.6  671.0  12.3  13.4 

During the year the Group repurchased 52.9m ordinary 2p shares with an aggregate nominal value of £1.1m at a total cost of £244.9m for which it paid cash at an average cost per share of £4.64. These shares were cancelled.

During the year 16.4m ordinary 2p shares with an aggregate nominal value of £0.4m were issued under share option schemes for a total consideration of £50.4m.

  2006 
Million 
2005 
Million 
2006 
£m 
2005 
£m 
Ordinary shares of 2p each        
At 1 January 16.9  8.6  0.4  0.2 
Shares repurchased 8.3  0.2 
Share cancelled (16.9) (0.4)
At 31 December 16.9  0.4 

During the year the company cancelled the shares held in treasury.

The Group has an unexpired authority to repurchase up to 10% of its issued share capital.