apportion vs retain

apportion

verb
  • To divide and distribute portions of a whole. 

  • Specifically, to do so in a fair and equitable manner; to allocate proportionally. 

retain

verb
  • To employ by paying a retainer. 

  • To hold back (a pupil) instead of allowing them to advance to the next class or year. 

  • To keep in one's pay or service. 

  • To keep in possession or use. 

  • To hold secure. 

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