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168:). 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.
188:, 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.
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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.
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240:"Programming pearls: Bumper-Sticker Computer Science"
181:, in which it was titled the "Rule of Credibility".
56:. Unsourced material may be challenged and removed.
175:'s September 1985 "Programming Pearls" column in
19:For the American educational funding policy, see
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116:Learn how and when to remove this message
16:Humorous aphorism in computer programming
287:Mantle, Mickey W.; Lichty, Ron (2012),
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290:Managing the unmanageable
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186:agile software projects
334:Programming principles
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238:Bentley, Jon (1985).
134:software engineering
130:computer programming
65:"Ninety–ninety rule"
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257:10.1145/4284.315122
339:1985 introductions
293:, Addison Wesley,
138:ninety-ninety rule
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173:Jon Bentley
154:Tom Cargill
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21:90–10 rule
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158:Bell Labs
106:June 2017
192:See also
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319:Adages
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