commutable vs exchangeable

commutable

adj

  • Capable of being commuted. 

exchangeable

adj

  • Able to be exchanged. 

  • Having an associated right to be exchanged for another form of financial security. 

noun

  • Any financial instrument with an associated right to be exchanged for another form of financial security. 

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