affidavit vs documentation

affidavit

noun
  • A signed document wherein an affiant makes a sworn statement. 

documentation

noun
  • Something transposed from a thought to a document; the written account of an idea. 

  • Documents that explain the operation of a particular machine or software program. 

  • Documentary evidence and sources. 

  • Comments that explain the usage of individual functions, libraries and blocks of code. 

  • A documentary. 

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