The credit card issuer increased its credit loss provision by 5% and also took a $1.77 billion hit from the new tax law.
The credit ratings agency forecast that the junk default rate will be 4% this year, up from 3.5% in 2015.
S&P estimates that China's corporate debt pile, now at 160% of GDP, will climb 77% to $28.8 trillion over the next five years.
