# Understanding Progress Calculation in Primavera at the WBS Level

When working with Primavera P6, you may have questioned why the Activity % Complete does not roll up (total) at the Work Breakdown Structure (WBS) level.

This article will explore the reasons behind this and shed light on how Primavera P6 handles progress calculations.

Contents

## Different Units of Measure

One crucial aspect to consider is that each activity in Primavera P6 can have its unique unit of measure.

For example, the Excavation activity may use cubic meters (M3) as its unit, while the Form/Pour Concrete Slab activity may employ square meters (M2), and the Install Underground Water Lines activity might adopt meters (M) as its unit.

## The Challenge of Incompatible Units

Since these activities utilize different units of measure, they cannot be directly summed up to calculate the total progress. Primavera P6 does not automatically aggregate the Activity % Complete at the WBS level due to the lack of compatibility for direct summation.

## Progress Calculation in Primavera P6

In Primavera P6, progress is typically tracked for each activity based on its specific unit of measure. The total progress value for each activity is then rolled up to higher levels in the project hierarchy, such as the WBS or project level, considering the activity’s weighted values or Earned Value Cost calculations.

## Importance of Unit Price and Cost Calculations

Suppose You want to understand progress at the WBS level accurately. In that case, it is crucial to know the unit prices for each activity and calculate the total cost for each activity accordingly.

By factoring in these unit prices and costs, you can obtain a comprehensive view of the project’s overall progress using the Earned Value Cost analysis.

## Conclusion

In Primavera P6, the absence of rolled-up Activity % Complete at the WBS level stems from the different units of measure employed by individual activities.

By understanding this aspect and considering unit prices and costs, project managers can ensure better progress analysis at the WBS or Project level in Primavera P6.