This excerpt taken from the JBLU 8-K filed Oct 12, 2005.
Depreciation Expense for Leasehold Improvement: Improvements made to leased space should be depreciated over their related lease term or their useful economic life, whichever is shorter. Historically, we had assumed renewal of our leases for airport space and depreciated these improvements over their
expected useful economic lives. Based on recent interpretative guidance from the Securities and Exchange Commission staff, we have restated our financial statements to reflect depreciation of our leasehold improvements over the shorter of their economic lives or their remaining lease terms, including any reasonably assured renewal periods. This adjustment resulted in $0.3 million and $0.2 million increased depreciation expense in 2003 and 2004, respectively.