Fri. vs Friday

Fri.

Friday

adv
  • On Friday. 

noun
  • The sixth day of the week in many religious traditions, and the fifth day of the week in systems using the ISO 8601 norm; the Muslim Sabbath; it follows Thursday and precedes Saturday. 

  • The last workday in a work schedule that is not Monday through Friday. 

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