In 2007 I can use the WorksheetFunction.NetworkDays to find the number of business days between two dates.
However, when the code is run on another PC running 2003 (without the Analysis ToolPak) I get an error.

My users are likely to grumble if I ask them to configure something in Excel before they can run my stuff.
Is there anyway to reference the Analysis Toolpak from VBA if it hasn't been installed?

Alternatively, does anyone have any code that replicates this function so I can bypass the issue?