Portfolio: reading workload variances by project
Progress in percent says where a project stands. Workload variance says how much more it costs than planned. At portfolio level, it is often the most useful indicator for making trade-offs.
Including +6 h reported by Lola on the new site preparation
A portfolio review often starts with progress: 48%, 35%, 67%. Those figures say where the projects stand. They do not say which ones are drifting.
What a workload variance is
Workload variance compares two numbers of hours: what the project was supposed to require, and what it will require according to the latest reports. Time already spent plus reported remaining work, minus planned workload. A positive variance means the project is consuming more than planned.
Where those hours come from
A project's variance is not an estimate made in a steering committee. It is the sum of its tasks' variances, reported by the people doing the work. When Lola reports 8 hours remaining instead of 2, those 6 hours flow up to the portfolio, with no re-entry.
Reading the portfolio
In our example, the line relocation shows +106 hours, the workshop extension study +56 hours, the packaging line installation +45 hours. The overhead crane replacement is finished. The first project is not the furthest behind in percentage, but it is the one consuming the most extra capacity: that is where the trade-off matters.
Key points
- the percentage says where a project stands, the variance how much more it costs;
- the variance is calculated from the team's reports, not from an overall estimate;
- at portfolio level, variance is what guides trade-offs.