Full-year US economic growth slowed to 1.9 per cent – from 2.8 per cent in 2012 – in 2013 despite a strong second half, according to fourth quarter initial estimates by the US Bureau of Economic Analysis.The slowdown last year was due to a large decrease in federal government spending after an austerity budget took effect in March.Other causes were slower growth in personal consumption, commercial real estate investment and exports, the bureau said.