Compute your own holidays

Excel formulas such as NETWORKDAYS and WORKDAYS use holidays. You can type these out manually but if your application goes on long enough (I have a couple of apps that have been used in one form or another for over a decade), the application eventually outlives the holiday list. One solution is to compute the holiday list dynamically. For my apps this means last year, this year and next year's holidays.

The attached has a "minimalist" list of holidays. If you need to compute more, see this blog: http://www.cpearson.com/excel/DateTimeWS.htm.

What I do is open this sheet in the same instance of Excel with the application that needs the list, and copy and paste it in. I call Range A1:A21 "Holidays" and go on with programming. Since the dates I use are after 1906 I am not concerned with the formulas mistaking the years for holiday dates.

Easter (Good Friday, Mardi Gras) is a toughie. You will have to look on the web for an application that calculates the dates for it.

Also the application doesn't address the case where holidays are based on a lunar calendar. I'd like to see tools to manage that.