NOTES TO THE CONSOLIDATED ANNUAL FINANCIAL STATEMENTS l NOTE 8
    2013
Rm
  2012
Rm
 
8. Transport fleet          
  Cost 9 808     8 659  
  Accumulated depreciation and impairment 5 182     4 323  
    4 626     4 336  
  Net book value at beginning of year 4 336     3 627  
  Net acquisition of subsidiaries and businesses 72     418  
  Additions 891     1 045  
  Proceeds on disposal (300)     (232)  
  Depreciation (704)     (601)  
  Impairment charge (4)     (3)  
  Profit on disposal 20     8  
  Currency adjustments 268     48  
  Fair value adjustments on disposal group       (5)  
  Reclassifications 47     31  
  Net book value at end of year 4 626     4 336  
  Depreciation is calculated on a straight-line basis to write off the cost of each component of the transport asset to its residual value over its estimated useful life between 3 to 12 years.

Certain transport fleet assets have been encumbered as security for interest-bearing borrowings amounting to R274 million (2012: R200 million), (refer to note 23).

The total value of transport fleet assets held under capitalised finance leases included above is R197 million (2012: R147 million).