ebb tide vs impairment

ebb tide

noun
  • The period between high tide and the next low tide in which the sea is receding. 

impairment

noun
  • A downward revaluation, a write-down. 

  • A deterioration or weakening 

  • The result of being impaired 

  • A disability or handicap 

  • an inefficient part or factor. 

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