Difference between two stardates

<%
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    ' 94305, USA.
 
    ' Calculate the difference between two stardates.
    function stardatediff(firstStardate, secondStardate)
        dim years
        dim years1
        dim years2
        dim days
        dim days1
        dim days2
        dim hours
        dim hours1
        dim hours2
 
        years1 = mid(firstStardate, 0, 2)
        years2 = mid(secondStardate, 0, 2)
 
        days1 = mid(firstStardate, 2, 3)
        days2 = mid(secondStardate, 2, 3)
 
        hours1 = mid(firstStardate, 6, 1)
        hours2 = mid(secondStardate, 6, 1)
 
        if years1 > years2 then
            years = years1 - years2
        else
            years = years2 - years1
        end if
 
        if days1 > days2 then
            days = (days1 * 366 / 1000) - (days2 * 366 / 1000)
        else
            days = (days2 * 366 / 1000) - (days1 * 366 / 1000)
        end if
 
        if hours1 > hours2 then
            hours = (hours1 * 144 / 60) - (hours2 * 144 / 60)
        else
            hours = (hours2 * 144 / 60) - (hours1 * 144 / 60)
        end if
 
        days = round(days)
        hours = round(hours, 1)
 
        stardatediff = "There are $years years, $days days, and $hours hours between Stardate $firstStardate and Stardate $secondStardate."
    end function
%>