The market for U.S. corporate borrowing via commercial paper contracted by the most in 19 months, led by a plunge in the amount of issuance from non-financial companies, amid signs economic growth is slowing.

The seasonally adjusted amount of U.S. commercial paper slid $35.8 billion to $972.5 billion outstanding in the week ended Wednesday, the Federal Reserve said yesterday on its website. It's the biggest drop since a $44.3 billion contraction for the period ended Dec. 1, 2010, and the lowest level since $966.4 billion for the week ended May 9, according to Fed data compiled by Bloomberg.

Industrial firms may have chosen to reduce their reliance on short-term funding for reporting purposes at the close of the second quarter, according to Anthony Carfang, a partner at Treasury Strategies. Investors in the commercial paper market are concerned that Europe's debt crisis may spread, degrading corporate creditworthiness worldwide. The European Central Bank cut interest rates to a record low today and said it won't pay anything on overnight deposits as fiscal upheaval threatens to drive the euro region into recession.