A New Multivariable Grey Convolution Model Based on Simpson’s Rule and Its Applications

Table 7

E-waste, population density, and median household income in case three.

(year)	E-waste	Population density	Median household
	(tons)	(people/se mi)	Income ($)
2003	18108.19	92.07	46967.25
2004	27341.56	93.30	49585.35
2005	35887.90	94.66	50004.20
2006	46126.41	96.48	53522.31
2007	53737.51	98.06	56141.32
2008	62071.46	99.31	57857.52
2009	69246.27	100.27	55458.05
2010	68777.91	101.19	54888.45
2011	69673.02	101.84	55500.26
2012	73851.24	102.59	56443.76
2013	65894.78	103.56	57283.94
2014	67822.93	104.85	60153.00
2015	72103.41	106.26	63439.20