The bewildering lackofuniformity is a product of what industry pundits have come to call "vanity sizing"--a thinly veiled attempt by retailers to make weight-conscious customers feel better about their figures.
Though efforts continue to be made for greater emissions standardization, questions remain about the validity of many of the voluntary offsets that have been purchased and sold to date in the United States due to a lackofuniformity around methodology, monitoring, and verification.