The provision for credit losses declined $1.9 billion from the fourth quarter of 2012 to $336 million, driven by improved credit quality. Net charge-offs declined significantly to $1.6 billion in the fourth quarter of 2013 from $3.1 billion in the fourth quarter of 2012, with the net charge-off ratio falling to 0.68 percent in the fourth quarter of 2013 from 1.40 percent in the year-ago quarter. The provision for credit losses in the fourth quarter of 2013 included a $1.2 billion reduction in the allowance for credit losses, compared to a $900 million reduction in the allowance in the fourth quarter of 2012.Noninterest expense was $17.3 billion, compared to $18.4 billion in the year-ago quarter, driven primarily by reduced expenses in Legacy Assets and Servicing (LAS) and lower personnel expense as the company continued to streamline processes and achieve cost savings. This was partially offset by higher litigation expense reflecting continued evaluation of legacy exposures largely related to residential mortgage-backed securities (RMBS) litigation. Litigation expense rose to $2.3 billion in the fourth quarter of 2013 from $1.1 billion in the third quarter of 2013 and $916 million in the fourth quarter of 2012. In addition, the year-ago quarter included a $1.1 billion expense related to the Independent Foreclosure Review (IFR) acceleration agreement. Income tax expense for the fourth quarter of 2013 was $406 million on $3.8 billion of pretax income, compared to an income tax benefit of $2.6 billion on $1.9 billion of pretax loss in the year-ago quarter. The effective tax rate for the quarter of 10.6 percent was driven by recurring tax preference items and certain discrete tax benefits. At December 31, 2013, the company had 242,117 full-time employees, down 9 percent from the year-ago quarter. Business Segment Results The company reports results through five business segments: Consumer and Business Banking (CBB), Consumer Real Estate Services (CRES), Global Wealth and Investment Management (GWIM), Global Banking, and Global Markets, with the remaining operations recorded in All Other.