duration vs solar day

duration

noun
  • An amount of time or a particular time interval. 

  • The time taken for the current situation to end, especially the current war 

  • A measure of the sensitivity of the price of a financial asset to changes in interest rates, computed for a simple bond as a weighted average of the maturities of the interest and principal payments associated with it. 

solar day

noun
  • one day of solar time, the time between successive noons; the time in which a planet such as Earth apparently rotates once around its axis, relative to the sun (on Earth about 24 hours as an average - the length of solar day is not constant throughout the year) 

How often have the words duration and solar day occurred in a corpus of books? (source: Google Ngram Viewer )