favorable impact of the previously mentioned items was partially offset by the full year impact of 2007 acquisitions, including, but not limited to, 18 German bottling and distribution operations, NORSA, glacéau, CCBPI and Leao Junior. Refer to Note 20 of Notes to Consolidated Financial Statements. In addition to the full year impact of prior year acquisitions, our 2008 gross profit margin was also unfavorably impacted by increases in the cost of raw materials and freight. 

Our gross profit margin decreased to 63.9 percent in 2007 from 66.1 percent in 2006. The decrease in our gross profit margin in 2007 was primarily due to the partial year impact of acquisitions made during 2007, including, but not limited to, 18 German bottling and distribution operations, NORSA, glacéau, CCBPI and Leao Junior. In addition to the partial year impact of 2007 acquisitions, the full year impact of the acquisition of CCCIL and the consolidation of Brucephil during 2006 also contributed to the decline in our 2007 gross profit margin. Refer to Note 20 of Notes to Consolidated Financial Statements. Our 2007 gross profit margin was also unfavorably impacted by increases in the cost of raw materials and freight. 

Selling, general and administrative expenses increased $829 million, or 8 percent, in 2008 compared to 2007. This increase was primarily attributable to the impact of foreign currency fluctuations, which accounted for approximately 4 percent of the total increase in selling, general and administrative expenses. In addition to the impact of foreign currency fluctuations, the increase in advertising expenses reflected the Company's continued investment in our brands and building market execution capabilities. Selling expenses increased primarily to support our bottling operations. In addition to the previously mentioned items, the increase in selling, general and administrative expenses in 2008 was also partially attributable to the full year impact of bottlers and brands acquired during 2007. Refer to Note 20 of Notes to Consolidated Financial Statements. These increases were partially offset by a decline in general and administrative expenses, primarily due to expense management and productivity initiatives. In addition, general and administrative expenses during 2008 also benefited from the full year impact of amendments made to the U.S. retiree medical plan and other employee benefit related costs during 2007. Refer to Note 16 of Notes to Consolidated Financial Statements for further discussion of the amendments made to the U.S. retiree medical plan during 2007. 

Stock-based compensation expense benefited from the reversal of previously recognized expenses related to performance based long-term incentive plans due to our revised outlook of the impact of foreign currency fluctuations in future years. Refer to the heading "Liquidity, Capital Resources and Financial Position—Foreign Exchange" for further discussion of the anticipated impact of foreign currency fluctuations. 

As of December 31, 2008, we had approximately $368 million of total unrecognized compensation cost related to nonvested share-based compensation arrangements granted under our