haczek (1995) vs inverted circumflex

haczek (1995)

inverted circumflex

noun
  • A dipping tone. 

  • Any diacritic obtained by rotating a circumflex (ˆ) 180°. 

  • A háček. 

How often have the words haczek (1995) and inverted circumflex occurred in a corpus of books? (source: Google Ngram Viewer )