Askam in Furness vs Letchworth Garden City

Askam in Furness

name

  • Synonym of Askam, Cumbria, England. 

Letchworth Garden City

name

  • Synonym of Letchworth, Hertfordshire, England. 

How often have the words Askam in Furness and Letchworth Garden City occurred in a corpus of books? (source: Google Ngram Viewer )