private List<Double> getTaskLagDeviations() {
if (this.getRootTask() == null) {
throw new RuntimeException("Root task is null");
}
CalculateFinishedTasksLagInCompletionVisitor visitor = new CalculateFinishedTasksLagInCompletionVisitor();
TaskElement rootTask = getRootTask();
rootTask.acceptVisitor(visitor);
return visitor.getDeviations();
}