IBM System 360 Mod 70 info

Philip Belben philip at
Sat Jul 26 12:21:44 CDT 2008

>> Who wrote ""the first 50 percent of a project takes 90 percent of
>> the time.  The remaining 50 percent of the project takes the other
>> 90 percent of the time."?   Not from TMMM, I know.
>> Cheers, Chuck
> I thought that was 10% rather than 50%.

I agree about the 10%.  I know it as the Ninety-ninety Rule of Project
Schedules.  "The first 90% of the work takes the first 90% of the time.
The last 10% takes the other 90%."

I can't remember where I encountered it.  It was either in the magazine 
"Micrcomputer Printout" that flourished in the UK from 1978 to 1983, or 
in one of the paperback "Murphy's Law" books.

In either case that was early 1980s, and the joke wasn't new then.


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