The most significant concern Citi Private Bank's global head of managed investments has for 2016 is a significant change in Chinese economic data that shows the country's growth is materially weaker, he told CNBC's "Squawk Box" on Monday.
"If you take a look at the market in China in the last year and how volatile it was and where it ended up, it was a difficult year and very year in that market for the entire time. The question is what does the real data look like," said David Bailin, who manages about $65 billion in alternative and traditional assets for wealthy clients at Citi.
Citi's view is that the Chinese economy is growing at 4 to 5 percent, he added. That is below government targets near 7 percent.
Chinese stocks plunged Monday, spurring a trading halt for the rest of the session, and leading stock markets in Asia-Pacific lower after feeble manufacturing surveys revived concerns over the mainland's economic slowdown. Global markets followed Asian stocks lower.