Just when you thought it was safe to go back into the credit market waters, fresh data comes along for the bears to sink their teeth into.

The Federal Reserve's “Senior Loan Officers Survey,” released earlier this week, showed banks tightened lending standards over the past three months at the fastest rate since the middle of 2016, according to Citigroup Inc. strategists. They warn of an unhealthy turn for businesses accustomed to easy-money loans, with expansion plans on ice and debt loads becoming harder to service.

The surprise tightening has sparked a wave of analyst commentary, given the survey is generally considered a leading indicator for economic growth in the United States, even prompting Citi analysts to revise their default forecast.