(8) Other Intangible Assets

in th. euros   31.12.2008   31.12.2007
Customer bases   12,957   12,383
Brands   2,879   3,187
Customer service contracts   286   475
Proprietary software   67   100
Acquired software   3,370   3,069
Other intangible assets   19,559   19,214

The brands have an unlimited useful life and are allocated to the cash-generating unit IT e-commerce. In the reporting period, an impairment amounting to the full book value of 600 thousand euros (IAS 36) has been recognised for the Dutch brand Artikona under depreciation and amortisation and thus under operating expenses, as this brand will no longer be used due to a name change and therefore will no longer contribute to the cash flow. In contrast, the value of the other brands is not impaired in any way.

By means of sensitivity analyses we have established that, even in the event of key assumptions differing within a realistic framework, there would be no need for an impairment of brands. The discount rate applied for the determination of the utilisation value of the brands within the scope of the impairment tests reflects the asset-specific risks.

Customer Bases    
Carrying amount (31.12.2008)   12,957
Remaining useful life (weighted average)   3.5 years
Accumulated depreciation by budgeted amounts   14,110
Accumulated impairment as per IAS 36   269
Differential on currency translation of accumulated depreciation   670
Scheduled depreciation 2008   3,375

The statement of changes in other intangible assets is given in detail in Appendix B and C to the notes.