American households’ outstanding debt climbed to an all-time high of $ 13.1 trillion in the October-December period, according to data released Tuesday by the Federal Reserve Bank of New York. It marked the fourth straight quarter in which borrowing reached a record. Debt balances increased by 3.2 percent in credit-card borrowing, which was the second-largest since 2007 and a record level of auto loans. At the same time, 7.55 percent of credit-card balances were in serious delinquency – those 90 days or more due – the highest since the first quarter of 2016, while the 4.05 percent delinquent share of car loans was the biggest since 2012 . The overall share of 90-day delinquent loans fell to 3.12 percent from 3.19 percent in the mortgage and student loan levels.