Official Chinese foreign exchange reserves peaked at $4 trillion in June 2014 and fell all the way to $3.2 trillion this past January. This is being portrayed in some quarters as a crisis; it's not.
But it is something of a problem, and might have an impact on the US if loss of reserves took the form of selling Treasuries. The much-watched "major foreign holders" series puts direct ownership by China at almost exactly the same level in December 2014 as December 2015, a pronounced stability which occurs all too frequently in Chinese numbers.
Meanwhile Belgium, which saw an oh-so-mysterious rise in 2014 when China's reserves were still expanding, had holdings of Treasuries plunge more than $200 billion over the course of 2015 when China's reserves contracted. In recent years, most nominally Belgian transactions in American bonds have been understood to be ultimately conducted by or for Chinese parties.