DateDiff to calculate workdays but not include specific dates

[farmera]

thread1462-1527034

I want to add to the formula in the referenced thread and ask it not to include a list of holiday dates in the calculation. I'm thinking of using an IF statement but am really new to programming. I'm using Crystal XI to pull from an Oracle 10g database.

The following is the referenced formula and works. I just need to expand on it to not count holidays.
{@MonthStart} and {@MonthEnd} are Crystal formulas.

DateDiff ("ww",({@MonthStart}),({@MonthEnd}), crMonday) +
DateDiff ("ww",({@MonthStart}),({@MonthEnd}), crTuesday) +
DateDiff ("ww",({@MonthStart}),({@MonthEnd}), crWednesday) +
DateDiff ("ww",({@MonthStart}),({@MonthEnd}), crThursday) +
DateDiff ("ww",({@MonthStart}),({@MonthEnd}), crFriday)

Thanks for any ideas,

Farmera