Table 1.

Yearly mean NO₂ of different AQI monitoring stations.

NO2
Sl. no	AQI station	Parameter	2018	2019	2020	2021
1	Kolkata	Maximum	102	48	26	98
		Minimum	23	18	5	24
2	Delhi	Maximum	99	49	37	107
		Minimum	10	12	9	16
3	Patna	Maximum	57	34	29	61
		Minimum	10	9	5	12
4	Chennai	Maximum	68	57	49	62
		Minimum	24	21	12	21
5	Mumbai	Maximum	91	83	73	79
		Minimum	23	17	14	12
6	Ahmedabad	Maximum	46	39	31	50
		Minimum	12	9	8	15
7	Bengaluru	Maximum	57	49	42	62
		Minimum	11	24	21	14
8	Lucknow	Maximum	48	42	37	53
		Minimum	9	13	10	21
9	Muzaffarnagar	Maximum	105	95	82	97
		Minimum	21	14	15	13
10	Guwahati	Maximum	31	28	21	34
		Minimum	8	9	10	9