UCL/APM Principles of Project Management graham.collins@ucl.ac.uk UCL/APM Principles of Project Management Earned Value (EV) Graham Collins University College London (UCL) graham.collins@ucl.ac.uk Lecture 7 Earned Value 1st March 2007
Example iterative project Iteration Month Planned Costs 1 5000 2 8000 3 7000 4 12000 5 14000
Question After 5 months, it is found that activities 1-4 have been completed, and that the spend is £36000. Using a measure that simply looked at spend, the target was to have completed five activities during this time and therefore the spend should be £46000
Calculating Earned Value Value is ‘earned’ by the completion of activities and the budget for each activity is the value it has earned. In this case it would be the sum of the budgets for the activities 1-4 ie £32000
Array of Measures Actual spend £36000 Planned spend £46000 Earned value £32000
cpi Cost performance indicator =earned value/actual spend =32000/36000 =0.889 Estimated cost at completion =original budget/cpi =£46000/0.889 =£51000 approx (Note that the variance between earned value and actual is £4000)
spi Schedule performance indicator =earned value/planned =32000/46000 =0.696 Estimated time of completion=Original time estimate/spi =5months/0.696 =7.2months (Note variance was £14000 between what was earned and planned)
Exercise Month Planned costs Actual costs iterations complete 1 50 40 0.5 2 60 50 1.5 3 70 60 2 4 90 90 2.5 5 100 110 3 6 90 70 3.5 The plan was to complete one iteration per month
Planned in comparison to Actual
Earned Value in relation to Planned costs and Actual costs
Variance
Exercise Should variance ie cpi and spi be plotted based on cumulative figures or per month? Recalculate based on monthly values
Variance tracked on a monthly basis
spi Note calculations for spi have used spic or cost. In the original example spic was EV/planned = 32/46=0.696 Final time to complete=original time estimate/spic 5 months/0.696 = 7.2 months spit or time is 4/5 (ie 4 months over 5) =0.8 therefore final time = 5months/0.8 =6.25 months
Further reading Agile & Iterative Development: A Manager’s guide Craig Larman 2004 Addison-Wesley (Agile Software Development Series) ISBN: 0-13-111155-8