Air Pollution and the Public Perception Level and Self-Protection Demand in Three Cities of China: Fractional Grey Modelling Analysis

Table 3

The estimated AQI from 2020 to 2024 in three cities.

	Growth rate	2020	2021	2022	2023	2024
Beijing	0.95	82	78	74	70	67
	0.97	83	81	78	76	74
	1.03	89	91	94	97	100
	1.05	90	95	100	105	110
	1.1	95	104	114	126	139
Tianjin	0.95	95	90	86	81	77
	0.97	97	94	91	89	86
	1.03	103	106	109	113	116
	1.05	105	110	116	122	128
	1.1	110	121	133	146	161
Shijiazhuang	0.95	108	103	98	93	88
	0.97	111	107	104	101	98
	1.03	117	121	125	128	132
	1.05	120	126	132	139	145
	1.1	125	138	152	167	184