# fn:years-from-duration - XPath XQuery Reference

Returns the number of years in a duration.deterministiccontext-independentfocus-independentIf $arg is the empty sequence, the function returns the empty sequence.Otherwise, the function returns an xs:integer representing the years
            component in the value of $arg. Given that a duration
            is a ($months, $seconds) tuple, the result is the value of ($months idiv 12).If $arg is a negative duration then the result will be negative.If $arg is an xs:dayTimeDuration the function returns 0.fn:years-from-duration(xs:yearMonthDuration("P20Y15M"))21fn:years-from-duration(xs:yearMonthDuration("-P15M"))-1fn:years-from-duration(xs:dayTimeDuration("-P2DT15H"))0