Currently your commute Statistics results (GHG, VMT and $ saved) are created by comparing your actual commutes to the Commute Snapshot you filled out in the registration process. What does that mean?
Your Commute Snapshot is the question that asked: "How do you typically commute to work each day?" If you stated that you take the bus every day, your Commute Snapshot baseline is going to reflect that. The Commute Snapshot at is considered your baseline, or the equivalent of 'zero'. So if you do take the bus every day (matching what you indicated in your Commute Snapshot), your results statistics will show 0.
If, however, you drove alone for a few days for any reason, or did not use a commute alternative as much as you indicated in your Commute Snapshot, your results it will show negative numbers. This is because it will show the added miles and GHG's that the driving alone created compared to when you were riding the bus every day. If you take the bus for more days than you said in your the snapshot it will reflect positive numbers that reflect the miles and GHG's that you reduced beyond your stated days in your the snapshot. These would be considered new trips reduced.
We are working on showing your GHG and Vehicle Miles Traveled statistics in a way that reflects the comparison to the baseline you set up in your registration and the reductions that you make by choosing an alternate commute choice in the first place. Both of these numbers are significant and our goal is to give you as clear a picture of your impact on the environment and your pocketbook as possible. We don't want doing the right thing to just equal zero.
If you have further questions please contact your program administrator.