below vs not so important as

below

prep
  • Unsuitable to the rank or dignity of; beneath. 

  • Downstage of. 

  • Lower in spatial position than. 

  • Lower than in value, price, rank, concentration, etc. 

  • South of. 

  • Downstream of. 

adv
  • On or to a lower deck, especially as relative to the main deck. 

  • On or to a lower storey. 

  • Later in the same text. 

  • In or to a lower place. 

  • Below zero. 

not so important as

How often have the words below and not so important as occurred in a corpus of books? (source: Google Ngram Viewer )