The US economy is humming under President Donald Trump - but is it sustainable?
S&P Global US chief economist Beth Ann Bovino says the US economy was doing well before the Trump administration took over the helm.
In the last quarter the US economy experienced 4.1 per cent GDP growth.
"When we look at the US economy we have job gains holding at around 200,000 jobs per month ... you have people spending, you have businesses investing significant amounts and that's all a positive thing but the worry of course is that the tax package and also the bipartisan budget agreement that also came in to place, the question is; 'are we going to see the productivity boost or are we going to just see inflation down the road?'," Bovino said.
Economists expect US growth to slow down by 2020.