amortization of intangible assets associated with businesses acquired during 2004.
Accretion expense. Accretion expense was $13.7 million and $12.7 million or, as a percentage of
revenue, .5% and .5%, for the years ended December 31, 2004 and 2003, respectively, versus $0 for 2002.
Accretion expense resulted from the adoption of SFAS 143 as of January 1, 2003. The increase in such
expenses in aggregate dollars in 2004 is primarily due to expansion of our landÑll operations.
Selling, General and Administrative Expenses. Selling, general and administrative expenses were
$268.3 million, $247.9 million and $238.7 million, or, as a percentage of revenue, 9.9%, 9.8% and 10.1%, for
the years ended December 31, 2004, 2003 and 2002, respectively. The increases in aggregate dollars are
primarily a result of the expansion of our operations through internal growth and acquisitions. The increase in
such expenses as a percentage of revenue from 2003 to 2004 is primarily due to higher compensation costs.
The decrease in such expenses as a percentage of revenue from 2002 to 2003 is primarily due to leveraging our
existing overhead structure over an expanding revenue base.
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