U.S. stock futures were down modestly on Friday, Feb. 15, as investors worried that weakening data from the world's two biggest economies could signal a deeper growth slowdown while eyeing the market impact of Donald Trump's decision to declare a national emergency after failing to win border wall funding from U.S. lawmakers. A twin set of inflation data from China underscored both export and domestic demand weakness in the world's second-largest economy, with factory gate inflation slowing for the seventh consecutive month in January -- to a 2016 low -- and consumer prices rising at the weakest pace in a year. The figures suggested China will struggle to reverse last year's broader economic slowdown, which was the worst in a decade.