upholstery vs wallcovering

upholstery

noun
  • The materials used in upholstering furniture. 

  • The craft or business of upholstering furniture. 

wallcovering

noun
  • A covering for a wall, such as wallpaper 

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