In a new year for world markets, the same old story in China has traders on edge.
Investors are worried that China — the world's second-largest economy — is slowing at a faster-than-expected pace. If the narrative sounds familiar, it is. The same fears about a Chinese slowdown riled global markets last summer.
A Monday sell-off in China triggered a drop in equities around the globe.
Here are the three reasons why China is again moving markets in a big way: