disturbance vs downtime

disturbance

noun
  • The act of disturbing, being disturbed. 

  • A noisy commotion that causes a hubbub or interruption. 

  • Something that disturbs. 

  • An interruption of that which is normal or regular. 

  • A serious mental imbalance or illness. 

downtime

noun
  • The amount of time lost due to forces beyond one's control, as with a computer crash. 

  • A period of time set aside for rest and relaxation; leisure time. 

How often have the words disturbance and downtime occurred in a corpus of books? (source: Google Ngram Viewer )