How is carbon Footprint calculated?

How is carbon Footprint calculated?
How To Calculate Your Carbon Footprint

Multiply your monthly electric bill by 105.
Multiply your monthly gas bill by 105.
Multiply your monthly oil bill by 113.
Multiply your total yearly mileage on your car by .79.
Multiply the number of flights you’ve taken in the past year (4 hours or less) by 1,100.

How To Calculate Your Carbon Footprint
  1. Multiply your monthly electric bill by 105.
  2. Multiply your monthly gas bill by 105.
  3. Multiply your monthly oil bill by 113.
  4. Multiply your total yearly mileage on your car by .79.
  5. Multiply the number of flights you’ve taken in the past year (4 hours or less) by 1,100.