Skate to where the puck is headed, not to where it's been - Wayne Gretzky
Forecasting future performance is the key to project management success, not reporting what happened last period. Earned Value alone cannot forecast the future. We need models of the underlying behavior, the probabilistic behavior of this model, and the statistics that support these probabilistic forecasts.
Without this information (not just data), you're driving in the rear view mirror. It can be done, but you'll run over the skunk and know it too late.
