I say vs oi

I say

intj
  • Used for emphasis, or when resuming after diversion or interruption. 

oi

intj
  • Said to get someone's attention; hey. 

  • An informal greeting, similar to hi. 

  • An expression of surprise. 

pron
  • I. 

noun
  • A working-class punk rock subgenre of the 1970s, sometimes associated with racism. 

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