text: To date in 2005, we have experienced a signiÑcant increase in fuel prices. We believe that cost of 
  operations as a percentage of revenue may continue to remain high depending upon the cost of fuel, health 
  insurance, risk insurance and other key components of our cost structure and general economic conditions. 
  
  *Depreciation, Amortization and Depletion of Property and Equipment.*Depreciation, amortization and 
  depletion expenses for property and equipment were $252.4 million, $233.8 million and $193.5 million, or, as a 
  percentage of revenue, 9.3%, 9.3% and 8.2%, for the years ended December 31, 2004, 2003 and 2002, 
  respectively. The increase in aggregate dollars from 2003 to 2004 is primarily due to the expansion of our 
  operations through internal growth and acquisitions. The increase in aggregate dollars and as a percentage of 
  revenue from 2002 to 2003 is primarily due to an increase in landÑll amortization associated with the adoption 
  of SFAS 143. The remaining increase from 2002 to 2003 is due to increased depreciation expense resulting 
  from capital expenditures, acquisitions and the purchase of equipment originally placed into service pursuant 
  to an operating lease. 