text: Depreciation expense of $4,442,000, $4,080,000 and $3,743,000 was recorded for the years ended December 31, 2003, 2002 and 2001, respectively. 
  
  **P A T E N T S**
  Cost for patents acquired is determined at acquisition date. Patents are amortized over the remaining lives of the individual patents, which are four to 14 years. 
  Patents are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. 
  
  **G O O D W I L L**
  Goodwill represents the excess of cost over the fair value of tangible and identifiable intangible net assets acquired. Through December 31, 2001, goodwill 
  was being amortized over 25 years. Beginning January 1, 2002, accounting for goodwill was changed to conform to Statement of Financial Accounting 
  Standards (“SFAS”) No. 142, “Goodwill and Other Intangible Assets” as outlined in Note 2. Annual impairment testing for goodwill is done in accordance 
  with SFAS No. 142 using a fair value-based test. Goodwill is also reviewed periodically for impairment whenever events or changes in circumstances indicate 
  a change in value may have occurred. 