highly significantp <0.0001
However, the past five-year trend (2015-2019) was different where, the daily average of PM 2.5 and PM 10 levels (2015-2019) were higher by 70 and 155% when compared with the same time period in 2020 (Phase I), which was highly significant (Kruskal-Wallis test, p <0.0001) (Fig.