off the top of head vs uncontrolled

off the top of head

uncontrolled

adj
  • Not controlled; not under control. 

  • Lacking the usual traffic control devices, such as traffic lights, pedestrian signals, pavement markings, traffic signs, or a crossing guard. 

How often have the words off the top of head and uncontrolled occurred in a corpus of books? (source: Google Ngram Viewer )