loop date calculation macro

i have a list of dates in column A, i need a macro that will tell excel to look at the date in cell A1 for example and if the date in cell A1 happens to be a weekend or US bank holiday it needs to populate the next business date in cell B1, if cell A1 is a business date, then just populate cell B1 with the same date....is there a macro that can do this?...it would need to do this for cells A1 to A??, on different sheets i would have column A populated down to different number of rows. so the macro would have to do some kind of looping i guess. I have a variable RowCount that i created that counts the number of rows that have data in it. lets say the value of the variable RowCount is 10, this means that the last row that has data in it in column A is row 10. so how would the macro look like that does this?

thanks