Have any countries successfully used carbon taxes to reduce their emissions?

After enacting carbon taxes, emissions declined in Finland, Denmark, Sweden and the Netherlands relative to those in other 13 European countries without carbon taxes. Finland was the only country where the drop in emissions was statistically significant, probably because it has fewer industries exempted from the tax. In the case of a province within a country, British Columbia's emissions have decreased between 5% and 8% since the introduction of carbon taxes in 2008. Analysts from the U.S. Department of the Treasury estimated that if the U.S. were to implement an economy-wide carbon tax starting at $49 a ton in 2019, emissions could be reduced by as much as 21% over 10 years.