Q: How are trips and miles saved calculated?

A: Trips saved represents the total number of trips avoided by participants, such as choosing not to drive alone. Miles saved is the total number of miles that were not driven alone, summed across all participants and trips.

Q: How are calories burned calculated?

A: Calories burned are estimated using general guidance from the U.S. Department of Health and Human Services.

Typical averages include:

• Walking: about 100 calories per mile
• Biking: about 50 calories per mile

These are general estimates. Actual calories burned will vary depending on factors such as speed, terrain, and individual body weight.

Q: How are CO₂ emissions and dollars saved calculated?

A: Savings are calculated by comparing each transportation mode to driving alone. CO₂ savings are calculated as the difference between emissions per mile for driving alone and emissions per mile for the selected mode. This reflects the reduction in emissions per person, per mile.

Cost savings are based on the difference between:

• The cost of driving alone, estimated at about $0.82 per mile
• The cost associated with the selected mode

The $0.82 per mile estimate comes from AAA and reflects the average cost of owning and operating a mid sized vehicle, including fuel, maintenance, insurance, and depreciation.

For shared modes such as carpool and vanpool, costs are divided among participants, resulting in lower per person costs.

Q: What are the standard emissions and cost values by mode?

A: The platform uses the following default estimates for emissions and cost per mile by transportation mode:

*CO₂ saved is calculated relative to driving alone, which is estimated at 400 grams per mile.
**Savings are based on Drive Alone values, divided by 2 for carpools and 5 for vanpools.

Q: Where do these numbers come from?

A: Driving costs are based on AAA estimates for cost per mile, which include total vehicle ownership and operating expenses. Transit emissions, including bus and rail, are based on data from the APTA and reflect per rider emissions, including energy use and operations.

Q: Do these values vary by organization?

A: Yes. These values are default estimates and may vary between organizations. Some organizations adjust emissions and cost assumptions to better reflect their local conditions. This can include factors such as regional fuel prices or differences in transit systems.

Q: What does this mean for you?

A: Choosing alternatives to driving alone can significantly reduce both costs and CO₂ emissions. Active modes such as walking and biking also provide health benefits through calorie burn. Shared modes such as carpooling and vanpooling reduce individual costs by spreading expenses across multiple riders.