Definition of "underreport"

underreport

verb
third-person singular simple present underreports, present participle underreporting, simple past and past participle underreported
1. To report a number falsely, making it smaller than it ought to be, especially to do so intentionally
  Quotations
  The FBI underreported its use of the USA Patriot Act to force businesses to turn over customer information in suspected terrorism cases, according to a Justice Department audit.
  March 9, 2007, Lara Jordan, Associated Press, Audit Slams FBI Use Of Patriot Act
2. As a group, to report something less frequently than it actually occurs