broaden vs straiten

broaden

verb
  • To make broad or broader. 

  • To become broad or broader. 

straiten

verb
  • To make strait; to narrow or confine to a smaller space. 

  • To restrict or diminish, especially financially. 

  • Rising costs put those on fixed incomes in straitened circumstances. 

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