trade deficit with China alone represented a loss of nearly 200,000 U.S. jobs. During this period, Wal-Mart was responsible for 9.3% of total U.S. imports from China, increasing the U.S. trade deficit by an estimated $17.1 billion. This represents about 200,000 jobs, most of them in the manufacturing sector (133,000). A 2014 story in The Guardian reported that the Wal-Mart Foundation was boosting its efforts to work with U.S. manufacturers. In February 2014, the Walmart Foundation pledged to support domestic manufacturers by buying worth of American-made products in the next decade. Between 2014 and 2017, the Walmart U.S. Manufacturing Innovation Fund gave $10 million in grants to research and academic institutions for projects that improve domestic manufacturing. For the 2020 fiscal year, Walmart reported that nearly two-thirds of its merchandise was made, assembled or grown in the United States. As of March 2021, Walmart pledged to buy an additional $350 billion worth of American-based items over the next decade. Effects on productivity A 2001 McKinsey Global Institute study of U.S. labor productivity growth between 1995 and 2000 concluded that "Wal-Mart directly and indirectly caused the bulk of the productivity acceleration" in general merchandise, representing 16 percent of total productivity growth in the retail sector. Walmart's transformative use of information technology, particularly in supply-chain management, is identified as a major reason for its impact on productivity per man hour. For every dollar spent by Walmart to improve its own technology, an estimated ten dollars has been invested by suppliers throughout its supply chain on their own systems and software. Economist Robert Solow has emphasized the importance of imitation and adaptation, as well as innovation. In addition to improving its own efficiency, Walmart's innovations have been adopted by its competitors so that they can compete. Labor relations With over 2.3 million employees worldwide, Walmart has faced a torrent of lawsuits and issues with regards to its workforce. These issues involve low wages, poor working conditions, inadequate health care, and issues involving the company's strong anti-union policies. In November 2013, the National Labor Relations Board (NLRB) announced that it had found that in 13 U.S. states, Wal-Mart had pressured employees not to engage in strikes on Black Friday, and had illegally disciplined workers who had engaged in strikes. Critics point to Walmart's high turnover rate as evidence of an unhappy workforce, although other factors may be involved. Approximately 70 percent of its employees