belt-tightening vs downgrading

belt-tightening

noun
  • A reduction in expenditure, often as a result of financial restrictions. 

adj
  • Causing or involving a reduction in expenditure. 

downgrading

noun
  • A downgrade; a reduction of a rating, as a financial or credit rating. 

How often have the words belt-tightening and downgrading occurred in a corpus of books? (source: Google Ngram Viewer )