assertive vs high-octane

assertive

adj
  • Boldly self-assured; confident without being aggressive. 

high-octane

adj
  • High powered, energetic, forceful or dynamic. 

  • Having a high octane number, good anti-knock characteristics; used in high performance vehicles. 

  • Highly intoxicating or caffeinated. 

How often have the words assertive and high-octane occurred in a corpus of books? (source: Google Ngram Viewer )