Earned Value = sum of planned values of completed work. So, for each activity you need to calculate value of completed work by multiplying planned value and percent completed, then sum all up.
Schedule Variance = the difference between the work completed and the work planned to be completed. SV = EV - PV.
So basicaly, when you calculate Schedule Variance, you ask yourself "I only completed so much work by now (Planned Value * Percent Complete) but should have completed that much (sum of Panned Value of all activities that should have been completed). Am I behind schedule (completed work is less than planned, SV is negative), on time (completed equals the amount of work that was planned, SV is zero), or ahead of schedule (completed more work than was planned, SV is positive)?"
Take a look at PMBOK Guide Table 7-1. Earned Value Calculations Summary Table on page 224.
Moderators: Yolanda Mabutas, Ahmed Amin, Scott Gillard, Mary Kathrine Padua, ERIC BARTLETT, Gail Freedman, Kevin Nason, Steven Mudrinich, PMP, Mark Wuenscher, PMP, John Wolverton, Tracy Shagnea, PMP, Jada Garrett
This interview with Simona Fallavollita (LinkedIn Profile) was recorded at the magnificient Project Management Institute (PMI)® Global Conference 2017 in Chicago, Illinois. We discuss the how, what, why and when of the changes that are coming to the PMP exam.