If you are looking for a real quick way to spot trouble in a project, the progress line is a vertical plot that provides the highest level view of schedule progress. Yes, it is a simple visual monitor for the project displaying exactly where you are ahead, behind, or on schedule. It’s great, in particular, for large projects where schedule discrepancy may not be easy to spot.
The strength of the Gantt chart is that it is a visual representation of the inner workings of a project schedule. Overlaid on top of the Gantt chart is the vertical progress line plot at the data date; another visual image of the schedule.
The strength of the progress line is its simplicity. It provides a high level vertical view of the schedule’s progress by connecting to the points of progress for each activity. If the line zigs to the left, the activity is behind in progress, if it zags to the right, the activity is ahead. A more generic term for this feature is a “dog-leg time now” line.
This article describes the progress line and demonstrates its application to a project schedule.
We have in Figure 1 our demonstration project that has been progressed several weeks into the schedule.
We can tell by inspecting the baseline bars on the Gantt chart and comparing them to the actuals bars when an activity is ahead or behind schedule. With the Gantt chart as it is we will need to inspect every activity to see whether it is ahead, behind, or on schedule. With the progress line we will get a much quicker overall view of project progress.
To insert or overlay a progress line on the Gantt chart right click anywhere on the Gantt chart and from the resulting menu select ‘Bar Chart Options’. In the Bar Chart Options dialog select the Progress Line tab, Figure 2.
In the ‘Baseline to use for calculating Progress Line:’ drop down menu select Primary Baseline. Toggle on the draw progress line based on difference between current and baseline activity’s and select Finish Date from the drop down menu. Click OK. You will now have a progress line overlaid on your Gantt chart displaying when activities finish ahead, behind, or on schedule, Figure 3.
Note on the progress line, Figure 3, all the progress line points to the right of the data date indicate activities finishing ahead of schedule. All the points to the left of the data date warn of activities finishing behind schedule. Last, all the points on the data date are either complete or on schedule. In this way the progress line provides a quick overview of the schedule progress and where to focus our further investigations.
In our demonstration schedule we note, in particular, activity W1060 Set Foundation, which is going to finish behind schedule. Likewise W1140 Install Fence and W1160 Lay Stoning activities are going to finish behind schedule. On the positive side activity W1090 Erect Steel Structures is ahead of schedule.
Note also that our last activity W1180 Substantial Completion is right on schedule. So the progress line quickly tells us we have a few issues but overall our schedule progress is fine.
The progress line is a simple visual plot overlaid on top of the Gantt chart that provides the highest and quickest perspective on schedule progress. It plots off the data date and easily shows whether your activity is ahead, behind, or on schedule by the data points either to the right, left, or on top of the data date.
This allows you to easily focus in on areas of your schedule that require further attention. The goal is to keep the progress line as straight and close as possible to the Data Date line. The progress line is one of the many Gantt chart visual features that make it such an insightful scheduling tool.