discouraging vs forbidding

discouraging

noun

  • discouragement 

adj

  • that causes discouragement 

forbidding

noun

  • The act by which something is forbidden; a prohibition. 

adj

  • Appearing to be threatening, unfriendly or potentially unpleasant. 

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