To rate a food product independent of the amount being consumed, we calculate the "improvement percentage" as follows:
Definitions
co2value_g = 2667
This is the CO2-equivalent value associated with your product. Our example product accounts for 2667 grams.
DFU = 0.32
Short for “Daily Food Unit”, this is the number of Daily Food Units associated with your product. Our example product has 0.32.
global CO2/DFU_g = 3894
This is the global CO2 divided by Daily Food Unit ratio, that we’ve calculated based on the millions of products that we’ve analyzed.
Result
Improvement percentage = 1 - (2667 / 0.32) / 3894 = -1.14
Hence this food is 114% worse than average.