The U.S.s entrepreneurial culture, long celebrated as a key element in the country’s economic success, is being threatened by several long-term trends, according to a paper from the Brookings Institution’s Robert Litan and Ian Hathaway. Over the past 30 years, U.S. business starts have slid downward, with many experts and policymakers offering their own explanations for the trend. Litan and Hathaway examine the data and note two possible causes: regional population decline and business consolidation. Though these trends seem unlikely to change in the near future, a new survey by the Kauffman Foundation suggests that underutilized abilities of women entrepreneurs could help boost business creation if properly supported.