As equities climb around the world, Chinese traders aren't celebrating.

The Shanghai Composite Index has fallen 3.9 percent this week, the worst performance among 93 global benchmark gauges tracked by Bloomberg and the steepest decline since January. It's not just the stock market. The yuan is trading around its lowest level against a basket of currencies since November 2014, while yields on corporate debt have risen for 10 of the past 12 days.