I begin with Comp stat observations for fiscal-years 2000–2008 meeting the following criteria: (1) publicly traded; (2)domestically incorporated; (3) non-financial, non-utility industry; and (4) at least three years of consecutive observations. I identify new derivatives users by searching the entirety of Form 10-K (extracted from the SEC's EDGAR database) for keywords relating to derivatives. Consistent with Guay (1999), a firm is a New User if it did not report a derivatives position when it first appears in the sample, but did report a derivatives position in a subsequent year. Firms enter the New User sample only when derivatives usage is first observed (after first observing no derivatives usage).