Documentation project metrics

The time to complete a project is dependent on many things. Thus, we cannot give you a cost until we know more about your problems. But, we can give you data from our documentation projects.

Project time is dependent on the number of screens

For each screen, dialog box, and tab in which users enter data, we estimate that on average 5 hours are necessary for documentation. This estimate is calculated from the project data. For a range of software documentation projects, we created user documentation for 543 screens in 389 project days. In most projects, the range is between 2 hours and 7 hours for each entry screen.

The cost of a documentation project is not directly dependent on the number of pages or topics in the documentation. The expected number of pages or topics is not a good metric for estimating the cost. However, some other experts say that costs are dependent on the number of pages or topics.

In an initial estimate, we do not analyse the complexity of the screens. All software has some screens that are simple and some screens that are complex. Initially, a simple count of the screens is sufficient. We do not count read-only screens and messages.

For projects of more than approximately 20 project weeks, possibly employ a full-time technical writer. To employ a technical writer, use a recruitment agency.

Elapsed time is dependent on your team

If your team answers our questions quickly, then the duration of a documentation project can be as short as 1.5 times the number of project days. For example, in projects 3o and 2c, when we waited for answers, we worked on other parts of the projects.

The duration of most projects is between 2 and 3 times the number of project days.

Sometimes, much time is necessary for small projects. For example, projects 1p and 1o were delayed. In both cases, the software was simple and the project was simple. However, the duration was long compared to the number of project days. These things caused the delays:

The software was not complete and there were delays with new versions of the software.
Customer personnel were not available to answer questions.

Project data

This section shows data for some software documentation projects.

Documentation metrics for printed documents
Ref.	Screens	Document type	Pages	Project days	Duration (days)
1p	20	User guide	23	8	65
2p	39	User guide	91	26	46
3p	54	User guide	48	18	137
4p	79	User guide	130	79	462 (66 weeks)
5p	110	User guide + reference manual	260	60	124

Documentation metrics for online documents
Ref.	Screens	Document type	Topics	Project days	Duration (days)
1o	14	User guide + reference	17	8	186 (27 weeks)
2o	37	User guide + reference	31	46	425 (61 weeks)
3o	59	User guide + reference	100	54	83

Documentation metrics for combined printed and online documents
Ref.	Screens	Document type	Pages or topics	Project days	Duration (days)
1c	41	User guide (printed) + reference (online)	34 (printed) 63 (online)	45	171
2c	90	User guide (printed) + reference (online)	32 (printed) 118 (online)	45	69

Page-based metrics for software documentation

Some experts write that the cost of a documentation project is dependent on the number of pages or topics. (This metric is not good because the number of pages is known only at the end of a project.)

For printed documentation, approximately 3 to 5 hours a page are necessary. For online documentation, approximately 4 to 6 hours a topic are necessary. (Stop Guesstimating, Start Estimating, Fredrickson Learning, http://fredricksonlearning.com/articles/stop-guesstimating-start-estimating/.)

For high-tech industries, 7 hours a page is a good estimate. (JoAnn T Hackos, Managing your documentation projects. John Wiley & Sons, 1994.)

For an excellent discussion, see Geoff Hart's article about estimating project times and costs (www.geoff-hart.com/resources/2006/estimating.htm).

Dilbert's colleague Tina the Tech Writer shows that the number of pages is not a good metric (http://dilbert.com/strip/2007-11-27).