century before the "boom years" were even over. Lowell, Massachusetts, once the center of textile production in the United States, was described in the magazine Harper's as a "depressed industrial desert" as early as 1931, as its textile concerns were being uprooted and sent southward, primarily to the Carolinas. After the Great Depression, American entry into the Second World War effected a rapid return to economic growth, during which much of the industrial North reached its peak in population and industrial output. The northern cities experienced changes that followed the end of the war, with the onset of the outward migration of residents to newer suburban communities, and the declining role of manufacturing in the American economy. Outsourcing of manufacturing jobs in tradeable goods has been an important issue in the region. One source has been globalization and the expansion of worldwide free trade agreements. Anti-globalization groups argue that trade with developing countries has resulted in stiff competition from countries such as China which pegs its currency to the dollar and has much lower prevailing wages, forcing domestic wages to drift downward. Some economists are concerned that long-run effects of high trade deficits and outsourcing are a cause of economic problems in the U.S. with high external debt (amount owed to foreign lenders) and a serious deterioration in the United States net international investment position (NIIP) (−24% of GDP). Some economists contend that the U.S. is borrowing to fund consumption of imports while accumulating unsustainable amounts of debt. On June 26, 2009, Jeff Immelt, the CEO of General Electric, called for the United States to increase its manufacturing base employment to 20% of the workforce, commenting that the U.S. has outsourced too much in some areas and can no longer rely on the financial sector and consumer spending to drive demand. Since the 1960s, the expansion of worldwide free trade agreements have been less favorable to U.S. workers. Imported goods such as steel cost much less to produce in Third World countries with cheap foreign labor (see steel crisis). Beginning with the recession of 1970–71, a new pattern of deindustrializing economy emerged. Competitive devaluation combined with each successive downturn saw traditional U.S. manufacturing workers experiencing lay-offs. In general, in the Factory Belt employment in the manufacturing sector declined by 32.9% between 1969 and 1996. Wealth-producing primary and secondary sector jobs such as those in manufacturing and computer software were often