apportion vs keep together

apportion

verb
  • To divide and distribute portions of a whole. 

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

keep together

verb
  • To strive to maintain a group; to prevent a group from separating; to remain together. 

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