EU The middle productivity trap: Why are less productive firms systematically lagging behind? Tilis 7 years ago https://www.brookings.edu/blog/future-development/2018/04/03/the-middle-productivity-trap-why-are-less-productive-firms-systematically-lagging-behind/?utm_campaign=Brookings%20Brief&utm_source=hs_email&utm_medium=email&utm_content=61867197