death duty vs property tax

death duty

noun
  • An inheritance tax or estate tax. 

property tax

noun
  • A tax, usually ad valorem, charged on the basis of the fair market value of property. The scope of taxable property varies by jurisdiction and it may include personal property in addition to real estate. 

How often have the words death duty and property tax occurred in a corpus of books? (source: Google Ngram Viewer )