A new study of the e-cigarette tax in Minnesota has verified the first rule of economics: the more something costs, the less people buy. The study's authors, mostly National Bureau of Economic Research economists, found Minnesota's tax levied on e-cigarettes “increased adult smoking and reduced smoking cessation in Minnesota.” Although the findings agree with previous studies, showing that higher taxes successfully reduce vaping, they also find that e-cigarette taxes have re-incentivized the use of conventional cigarettes.