2008 vs . 2007 revenues , net of interest expense declined primarily due to the gain in 2007 on the sale of certain corporate-owned assets and higher inter-segment eliminations partially offset by improved treasury hedging activities . operating expenses declined primarily due to lower restructuring charges in the current year as well as reductions in incentive compensation and benefits expense . discontinued operations represent the sale of citigroup 2019s german retail banking operations and citicapital