centralization vs compression

centralization

noun
  • The act or process of centralizing, or the state of being centralized; the act or process of combining or reducing several parts into a whole 

compression

noun
  • An increase in density; the act of compressing, or the state of being compressed; compaction. 

  • The cycle of an internal combustion engine during which the fuel and air mixture is compressed. 

  • The electronic process by which any sound's gain is automatically controlled. 

  • The deviation of a heavenly body from a spherical form. 

  • The process by which data is compressed. 

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