That American companies have been wadding up huge amounts of cash is no secret. What may be less well-known is that they're also accumulating debt at a much faster pace. Total debt among more than 2,000 nonfinancial companies swelled to $6.6 trillion in 2015, dwarfing the $1.84 trillion in cash on their balance sheets, according to a study released Monday by S&P Global Ratings. The ratio of cash to debt is the lowest it's been in about 10 years, or just before the global financial crisis. As financial markets came to grips with the prospect of higher rates ahead, corporate America went on a debt bonanza. Debt grew 50 times that of cash, with companies rolling up $850 billion of new IOUs compared to just $17 billion, or 1 percent, cash growth.

"This jump in debt reflects the scant resistance borrowers faced from yield-starved investors as companies pursued acquisitions and returned cash to shareholders," S&P credit analysts Andrew Chang and David C. Tesher wrote in the report. What's more, most of the cash is concentrated in the top 1 percent while most of the debt resides with the rest. Total cash balances outside the elite actually declined 6 percent; by contrast, the other 99 percent held $6 trillion of the total debt load. The top 1 percent (25 companies) now controls more than half the corporate cash, up from 38 percent five years ago. The cash-to-debt ratio fell to 12 percent among speculative-grade issuers, the lowest level since before the Great Recession.