Five-a-day campaign (5 portions of fruits + veggies), adopted by UK in early 2000s, as it reduces risk of heart disease & cancer, and intestinal benefits

Creates incentive + lowered prices vs. opportunity cost, difficult to calculate subsidy amount,

Demand for permits decrease as demand for companies' products decrease (no need so many permits) --> price drops, quantity stays the same.

Huge tax increase before you see a proportionally smaller reduction in quantity demanded (and hence quantity transacted)

China = one of 3 biggest CO2 emitters and faces pollution, Chinese EV companies (e.g. BYD, Nio, Xpeng) have received tens of billions of subsidies

Price incentive to reduce consumption, tax revenues vs. regressive, parallel markets, imperfect market info

Need big subsidy before big drop in price before quantity demanded increases by a little

flexibility + internalize externality vs. job losses, MNC shift production, hard to determine correct cap level

Legislations, educational campaigns, indirect taxes

E.g. 92% tax on e-cigarettes in Vermont, USA; previously only a standard sales tax which was cheaper than traditional cigs, ad valorem tax

international agreements, legislations, cap and trade schemes, carbon taxes, indirect taxes, educational campaigns etc.

a situation where degradation, depletion or destruction of a common access resource is caused by rivalry and over-consumption.