belt-tightening vs diminishment

belt-tightening

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

adj
  • Causing or involving a reduction in expenditure. 

diminishment

noun
  • The act of diminishing; reducing in size, quantity, or quality. 

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