It added that the firm's credit rating was dragged down by what S&P believed to be a "severe" decline in profitability at the firm. China Evergrande has been struggling with liquidity issues since last year. However, last week's news of an asset freeze refocused attention on the company's debt troubles. That brought its share price down to a four-year low. Year-to-date, Evergrande's share price has tumbled more than 60%.