Aug. 7 (Bloomberg) — U.S. speculative-grade companies are in the best position ever to meet their debt obligations as investors pour a record $43 billion into high-yield mutual funds and borrowers boost the cash held on balance sheets.

Moody's Investors Service said Aug. 1 its Speculative-Grade Liquidity-Stress index, which falls as corporations' ability to manage cash needs improves, dropped to 3.1 percent in July, beating the previous record low of 3.3 percent in May. The New York-based ratings firm sees the U.S. default rate peaking at 4 percent in October before falling to 3 percent by June 2013, below the historical average of 4.6 percent since 1992.

While the unemployment rate has held above 8 percent since February 2009, demand for high-yield, high-risk bonds has grown as investors speculate that the Federal Reserve will keep interest rates near zero through late 2014 to bolster the economic recovery. Credit Suisse Group AG boosted its forecast for returns this year to a range of 8 percent to 11 percent from 7 percent to 10 percent.