Relation between Overtime and Duration in MS PROJECT 2016


I have a question from oen of my Blog readers:

“Every time I allocate the whole work hours to overtime hours the Duration column turns into 0 and the start and finish dates and time are the same. Why?”

OK! I have to explain how MS PROJECT 2016


and I will create John, as Resource, and I will assign him to the Task:




Now I will switch to the Task Usage View, and I will show Task Form, as well.


As you can see, John is supposed to work 40 hours, 8 hours per day, during 5 days of Duration. Now, suppose, that John will work more than 8 hours per day, and you want to put those hours as Overtime work. Suppose that 20 hours will be overtime work:


After I click on OK button I will get:


As you can see, Duration is 2,5 days now. Why? MS Project calculates Duration according to next formula:

DURATION = (Work – Overtime Work) / Hours per day. In this case it is: DUARTION = (40-20)/8 = 20/ 8 = 2,5 days.

Now suppose that all 40 hours are overtime work:


As you can see, Duration is 0 days, according to formula Duration = (40-40) / 8 = 0 Days. This make no sense but you should consider that Overtime work is something like “off the Calendar). If you consider this option you should ask yourself: “Do I understand overtime work?” Overtime work has to be smaller than total work (Work field). Overtime work is something like: “How many hours of regular work, will be over it?”. If overtime work is same as regular work, than it is regular work, not overtime!

Hope this helps!


About Nenad Trajkovski

Location: Zagreb, Croatia Occupation: Project Manager Interests: Project Management and MS PROJECT He was born in Zagreb, Croatia at 1963. After completing his college he started working on projects in different business areas (banking, manufacturing, automotive industry, distribution, oil companies, etc.) developing and implementing ERP systems into different companies. He has got a lot of experience working with people in different business processes and also possesses great knowledge in information technologies and financial services. Today he works as a business consultant, adn Project Manager in PERPETUUM MOBILE d.o.o. Zagreb. He is a regular lecturer for Project Management in MS Innovation Center in Varaždin, Logosoft Sarajevo in Bosnia and Herzegovina and SEAVUS GROUP in Skopje Macedonia. He was named the best lecturer of WINDAYS 2008 while his lecture was also voted as the best. In addition, he was in TOP 10 lecturers at the MS SINERGY 2009 and MS VISIA 2009, 2010. Shares first place as the best lecturer of KulenDays 2009 and 2010 and PMI Conference 2009 in Zagreb. He is also a regular lecturer in the MS Community. He is a Certified Accountant and a PMP (Project Manager Professional) and a PMI-RMP (Risk Manager Professional), MCP, MCT, and Microsoft Certified Technical Specialist - Microsoft Project 2010. From 01.01.2012 awarded with MVP (Microsoft Most Valuable Proffesional - Microsoft Project)!
This entry was posted in Microsoft Project 2013, MS PROJECT 2010, MS PROJECT 2016, PMI, PRoject Management and tagged , , . Bookmark the permalink.

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