text: During 2004, our operating margins improved, primarily due to lower self-insurance expense. This beneÑt 
  was partially oÅset by increased costs for fuel, labor and subcontracting costs associated with the long-haul 
  transport of waste by third party vendors. The net expansion in our operating margin allowed us to achieve 
  diluted earnings per share of $1.53 during the year ended December 31, 2004. 
  
  24 