Theory and observation set out the conditions such that market prices of outputs and productive inputs select an allocation of factor inputs by comparative advantage, so that (relatively) low-cost inputs go to producing low-cost outputs. In the process, aggregate output may increase as a by-product or by design .  Such specialization of production creates opportunities for gains from trade whereby resource owners benefit from trade in the sale of one type of output for other, more highly valued goods. A measure of gains from trade is the increased income levels that trade may facilitate. 
The latest economic figures released by the Commerce Department's Bureau of Economic Analysis (BEA) indicate that real Gross Domestic Product increased % (annual rate) in the second quarter, in line with expectations. This represents an acceleration over the previous two quarters, each of which saw growth of below 2%. The bulk of last quarter's growth was due to personal consumption expenditures which contributed percentage points to this increase, while private nonresidential fixed investment contributed percentage points, on the strength of business' investment in industrial and information processing equipment. The past two quarters have been the strongest for business investment since 2014. The other components of GDP contributed little to last quarter's growth: net exports ( points), and government consumption and investment (), and change in private inventories ( points).