The ability of the largest U.S. companies to collect from customers and manage inventory improved just slightly in 2011, while payables performance worsened, according to the 14th annual working capital survey from REL Consulting, a division of The Hackett Group, Inc. (NASDAQ: HCKT), and CFO Magazine. Overall, working capital performance improved slightly for 1000 of the largest U.S. public companies in the REL/CFO analysis, and working capital performance remains near the best levels seen in the past decade. But in large part the improvement was due to revenue growth. The study found a tremendous improvement opportunity in working capital management. Companies in the study now have over $900 billion in excess working capital, a figure that represents nearly 7 percent of the U.S. Gross Domestic Product (GDP) and is the largest opportunity in this area in the past five years. Compared with top performers by industry, typical companies collect from customers 16 days slower, pay suppliers nearly 10 days earlier, and maintain nearly double the inventory, according to the REL/CFO analysis. The study also found that few companies have been able to generate sustainable long-term improvements to working capital performance. The REL/CFO research found that while U.S. companies are beginning to reinvest in anticipation of growth, with capital expenditures rising by just over 23 percent, they are also continuing to stockpile cash, in part by relying on low-cost debt. Cash on hand levels rose to nearly $1 trillion for the companies in the REL/CFO analysis, an all-time high. Total debt increased by 6.8 percent since 2010 as well. In addition, despite significant revenue growth, the REL/CFO study found that gross margins and EBIT margins were down slightly compared to 2010. Operating expenses were also up nearly 13%, outpacing revenue, driven largely by an increase in the cost of IT, finance, and other business services functions.