Currently being updated.
Automatic reload in seconds.

Subscribe: RSS Podcasts iTunes
Episode 1022             Episode 1024
Episode 1023

Ninety-ninety rule
Thu, 2020-Feb-20 01:26 UTC
Length - 2:22

Direct Link

Welcome to popular Wiki of the Day where we read the summary of a popular Wikipedia page every day.

With 920,879 views on Wednesday, 19 February 2020 our article of the day is Ninety-ninety rule.

In computer programming and software engineering, the ninety-ninety rule is a humorous aphorism that states:

The first 90 percent of the code accounts for the first 90 percent of the development time. The remaining 10 percent of the code accounts for the other 90 percent of the development time.

This adds up to 180%, making a wry allusion to the notoriety of software development projects significantly over-running their schedules (see software development effort estimation). The anecdote expresses both the rough allocation of time to easy and hard portions of a programming undertaking, and the cause of the lateness of many projects in their failure to anticipate their difficult, often unpredictable, complexities. In short, it often takes both more time and more coding than expected to complete a project.

The rule is attributed to Tom Cargill of Bell Labs, and was made popular by Jon Bentley's September 1985 "Programming Pearls" column in Communications of the ACM, in which it was titled the "Rule of Credibility". In some agile software projects, this rule also surfaces when a task is portrayed as "relatively done". This indicates a common scenario where planned work is completed but cannot be signed off, pending a single final activity which may not occur for a substantial amount of time.

This recording reflects the Wikipedia text as of 01:26 UTC on Thursday, 20 February 2020.

For the full current version of the article, see Ninety-ninety rule on Wikipedia.

This podcast is produced by Abulsme Productions based on Wikipedia content and is released under a Creative Commons Attribution-ShareAlike License.

Visit for our archives, sister podcasts, and swag. Please subscribe to never miss an episode. You can also follow @WotDpod on Twitter.

Abulsme Productions produces the current events podcast Curmudgeon's Corner as well. Check it out in your podcast player of choice.

This has been Geraint. Thank you for listening to popular Wiki of the Day.

For current episodes, or for the rest of the Wiki of the Day family of podcasts go here.

Archive Episodes:
1-100  101-200  201-300  301-400  401-500
501-600  601-700  701-800  801-900  901-1000
1001-1100  1101-1200  1201-1300  1301-1400  1401-1500
1501-1600  1601-1700  1701-1800  1801-1900  1901-2000
2001-2100  2101-2200  2201-2225
  Buy WotD Stuff!!

Feedback welcome at

These podcasts are produced by Abulsme Productions based on Wikipedia content.

They are released under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

Creative Commons License

Abulsme Productions also produces Curmudgeon's Corner, a current events podcast.

If you like that sort of thing, check it out too!

Page cached at 2023-06-06 03:49:44 UTC
Original calculation time was 4.0921 seconds

Page displayed at 2023-06-10 17:52:01 UTC
Page generated in 0.0026 seconds