day-to-day vs diurnally

day-to-day

adv

  • On a daily basis. 

noun

  • Ordinary, monotonous routine; that which is usual or mundane. 

adj

  • Happening every day. 

  • Subject to daily redetermination. 

  • Ordinary or mundane. 

diurnally

adv

  • Every daytime. 

  • By daylight. 

  • daily 

How often have the words day-to-day and diurnally occurred in a corpus of books? (source: Google Ngram Viewer )