A flattening yield curve means it's time to worry, but not panic, top economist says

The yield curve has flattened to its lowest level since June 2007 with the 10-year Treasury note yield only around 10 basis points above the 2-year note. Joseph LaVorgna , chief economist of the Americas at Natixis, says the move has him "very worried" about what comes next. "The yield curve has almost always forecasted the direction of trend growth, meaning when the curve flattens, growth with a lag tends to slow and vice versa when the curve steepens," LaVorgna told CNBC's " Trading Nation " on Tuesday.