belt-tightening vs diminution

belt-tightening

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

adj
  • Causing or involving a reduction in expenditure. 

diminution

noun
  • A lessening, decrease or reduction. 

  • a compositional technique where the composer shortens the melody by shortening its note values. 

  • The act or process of making diminutive. 

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