on thin ice vs speculative

on thin ice

prep
  • In a dangerous, hazardous, or delicate situation; at risk. 

adv
  • dangerously, hazardously, delicately 

speculative

adj
  • Pursued as a gamble, with possible large profits or losses; risky. 

  • Pertaining to financial speculation; Involving or resulting from high-risk investments or trade. 

  • Characterized by speculation; based on guessing, unfounded opinions, or extrapolation. 

How often have the words on thin ice and speculative occurred in a corpus of books? (source: Google Ngram Viewer )