I'm going to assume that you are looking for information on EV, one of the terms/metrics of Earned Value Management. EV is computed by summing all the planned values (PV) for any project tasks completed up to the point in time where you are taking the measurement. PV is the valuation of the work performed.
Let's say that you are painting four walls. You expect to use $50 of paint for each wall and take one hour to paint each wall. At the end of 2.5 hours, you have painted only two walls and spent $100. If this is the point where we measure the earned value, it is $125=$50 for one wall + $50 for the second wall + $25 for the half wall. You are behind budget and over time when we compare the plan to the actual.