hyperpyron vs shilling sign

hyperpyron

noun
  • A Byzantine coin in use during the late Middle Ages, replacing the solidus as the Byzantine Empire’s gold coinage. 

shilling sign

noun
  • The symbol '/' used in the United Kingdom before decimalisation to separate shillings from pence when writing out sums of money. (Examples: 7/6 = seven shillings and six pence; 7/- = seven shillings exactly.) 

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