overestimate vs step-up

overestimate

noun
  • An estimate that is too high. 

verb
  • To judge or calculate too highly. 

step-up

noun
  • An increase. 

  • A workout movement wherein one leg stands on an elevated surface and lifts in the concentric part the rest of the body up onto it to target – depending on angle and starting distance of the other leg and weights applied by the arms – the femoral and gluteal muscles variously. 

adj
  • That increases in stages. 

  • That increases a voltage. 

How often have the words overestimate and step-up occurred in a corpus of books? (source: Google Ngram Viewer )