Table 4 Panel unit root test

Variables	Statistics	z	p-value
PRICE	0.999	3.571	0.9998
PPG	0.173	−68.098	0.0000
JEONSE	0.996	3.320	0.9996
JPG	0.095	−74.943	0.0000
PJR	0.983	2.169	0.9850
PJRD	0.098	−74.674	0.0000
COMP	0.364	−52.305	0.0000