at the head of the line vs up front

at the head of the line

up front

adj

  • Open, honest; tending to disclose information; truthful. 

adv

  • At the beginning; before anything begins. 

  • At the front. 

  • In an attacking position. 

How often have the words at the head of the line and up front occurred in a corpus of books? (source: Google Ngram Viewer )