A spreadsheet named "NYSE Holidays" contains NYSE Planned Holidays for 2005
and 2006; containing data in columns A and B:

New Year's Day 01/01/05
Martin Luther King, Jr. Day 01/17/05
Washington's Birthday 02/21/05
Good Friday 03/25/05
Memorial Day 05/30/05
Independence Day 07/04/05
Labor Day 09/05/05
Thanksgiving Day 11/24/05
Christmas 12/26/05
New Year's Day 01/02/06
Martin Luther King, Jr. Day 01/16/06
Washington's Birthday 02/20/06
Good Friday 04/14/06
Memorial Day 05/29/06
Independence Day 07/04/06
Labor Day 09/04/06
Thanksgiving Day 11/23/06
Christmas 12/25/06

Cell A1 in spreadsheet "SPX" contains =TODAY()

Cell A2 contains:
=WORKDAY(A1,1,'C:\NYSE Holidays\[NYSE Holidays.xls]Sheet1'!$B$1:$B$18)

Subsequent cells A3 through A421 copy A2, except the first parameter
increments (e.g., A2, A3, ) as a result of dragging.

SPX column A now has all planned trading days from today through Dec 29,
2006; and excludes weekend days and Holidays.

My first attempt specified =WORKDAY(A1,1,'[NYSE Holidays.xls]Sheet1'!$B:$B)
as the Range; but this failed with a #NUM! result. Apparently, Excel was
unable to resolve a column as a Range. And requires a specific starting and
ending cell range as input (B1:B18).

Does this sound right?