jaggery vs palm sugar

jaggery

noun
  • A traditional dark-brown unrefined sugar made from palm tree sap which is used throughout South and Southeast Asia; (by extension) other types of unrefined sugar. 

  • A small-scale production plant that processes sugar cane to make sugar. 

palm sugar

noun
  • sugar made from the sap of various species of palm tree, family Arecaceae. 

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