Elaine Evans thinks this is interesting: You may want to consider including 0 as a valid number within your estimation range From Robert C. Martin Series from Agile Estimating and Planning by Mike Cohn Publisher: Prentice Hall Released: December 2007 Note trivial efforts. dot impact velocity and create false assumptions of future performance Share this highlight http://learning.oreilly.com/a/agile-estimating-and/18864061/ Twitter Facebook Google Plus Email Get Instant Access Now Start a Free Trial Have an account? Sign in. Minimise Unlock the rest of Agile Estimating and Planning and 30,000 other books and videos By clicking this box, you confirm that you have read and agree to the terms and conditions of our Membership Agreement, and you understand that when your trial period ends, you will be required to provide billing information if you wish to continue using the service. Unlock the rest of this book Start a Free 10-Day Trial loading Learn about Safari for Business Have an account? Sign in.