There is however some historic use of subtractive notation other than that described in the "standard": in particular for 17, for 18, for 97, and for 99. A possible explanation is that the word for 18 in Latin is "duodeviginti", literally "two from twenty", 98 is "duodecentum" (two from hundred), and 99 is "undecentum" (one from hundred). However, the explanation does not seem to apply to and , since the Latin words for 17 and 97 were "septendecim" (seven ten) and "nonaginta septem" (ninety seven), respectively.