Share-based payments
The cost of equity-settled transactions with employees is measured by reference to fair value at the date at which the right to the shares is granted. Fair value is determined by an external valuer using option pricing models.
The cost of equity-settled transactions is recognised, together with a corresponding increase in equity, over the period in which any performance or service conditions are fulfilled, ending on the date on which the relevant employees become fully entitled to the award (vesting date).
The income statement charge for a period represents the movement in cumulative expense recognised at the beginning and end of that period. No expense is recognised for awards that do not ultimately vest, except for awards where vesting is conditional upon a market or non-vesting condition, which are treated as vesting irrespective of whether or not the market or non-vesting condition is satisfied, provided that all other performance and/or service conditions are satisfied.