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PLASTIC BAG TAX IS INSANELY EFFECTIVE: THIS ONE IS FOR D.C. PEOPLE, as well as behavioral economists, who surely make up the rest of you: our beloved new five-cent plastic bag tax decreased plastic bag usage from 22.5 million to 3.3 million in thefirst month alone. Washington D.C. is now sparkly clean! We are so insane about taxes in this country. FIVE CENTS! Whatever. Some of us need to clean litter boxes and will continue to pollute like the dickens. [ Washington Post ]