Developing Spreadsheet Models
Recommended conventions and guidelines with Lotta Rosenkallums

©2004, Information Disciplines, Inc., Chicago

Background & purpose

Computerized spreadsheets offer an easy way to analyze numeric data, and sometimes also serve well for implementing very small databases. Although the leading spreadsheet processors support a common subset of nearly identical facilities, vendor competition (and the threat of lawsuits) has led to an irritating degree of incompatibility among them.

The pioneering spreadsheet processor, VisiCalc is no longer supported on modern platforms. Today more than a half dozen excellent products are available for desktop computers.

Casual and formal spreadsheet models -- the need for standards

Anyone in an organization can develop a spreadsheet model for his or her own use, either one-time or recurring. Such casual spreadsheet models may help you to do your day-to-day work, but must not become essential to the functioning of your department. Casual spreadsheets are not subject to any mandatory standards.

On the other hand many spreadsheet models are like non-trivial computer programs. Once they're developed, they get re-used, often by staff other than the original developer. Such formal spreadsheet models are subject to certain organization standards, conventions, and guidelines, in order to:

  • assure financial integrity and auditability,
  • facilitate future enhancements, perhaps by people other than the original developer
  • facilitate I.T. or vendor assistance if something doesn't work as expected,
  • minimize incompatibilities with future computing environments.
  • allow automated interfaces with related application systems.

Warning

Experience shows that many spreadsheets that begin as simple, casual, single-user models evolve gradually into complicated ones upon which an organization unit comes to depend. If you find yourself repeatedly adding enhancements to your model or showing others in your department how to use it, you should probably consider it to be a formal model, and follow the guidance below.

Although most spreadsheet processors are easy to use for simple tasks, they provide a rich repertoire of complicated features that challenge the skills of an experienced professional programmer. It's surprisingly easy to lose control of a spreadsheet model that grows incrementally. If you're unsure, ask your I.T. people for assistance before implementing the next feature.

Standards, conventions, and guidelines

Available now Coming soon
  • Macro and script programming

  • Return to IDI home page

    Last modified January 4, 2005