This decrease is mainly due to lower depreciation costs as major equipment in our pilot plant in Montpellier have been acquired in 1994 and 1995 and are now fully amortized, as well as a decrease in rental costs and property tax. We reported last year our investors relation expenses in sales and marketing, while this year expenses are included in the general and administration expenses. However, we believe sales and marketing expenses may increase in the future, reflecting the expansion of our sales and marketing organization both in the United States and in Europe. This decrease reflects a decrease in consulting and legal fees from the previous year. Net - Interest income is comprised of interest on available and restricted cash.
Interest expense is comprised of interest payable on long-term obligations.
Although a significant portion of our revenues are denominated in U.S. dollars, a substantial portion of our operating expenses are denominated in Euros. Gains and losses on the conversion to U.S. dollars of assets and liabilities denominated in Euros may contribute to fluctuations in our results of operations, which are reported in U.S. dollars. Most of our capital lease obligations are expressed in Taiwanese dollars. In the past, fluctuations of the parity of the Taiwanese dollar versus the Euro caused significant foreign exchange gains or losses and may continue to do so in the future. We cannot predict the effect of exchange rate fluctuations on future operating results.