Mexico City has taken several steps to try to improve air quality including restricting driving one or two days during the weekdays. The program hasn't had good results.
In 2008 the city added driving restrictions on Saturday hoping to improve air quality, but according to research made by Lucas W. Davis, an associate professor at UC Berkeley's Haas School of Business, this measure wasn't working.
Scientific Reports published in February this year that "Saturday Driving Restrictions Fail to Improve Air Quality in Mexico City" This study examines the effects of restricted driving on Saturdays by comparing pollution levels of eight major pollutants before and after the program application. The government thought that the Saturday program would reduce vehicle emissions 15% or more.
To determine the impact of Saturday restrictions, Davis Analyzed hourly air pollution data from 29
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