Table 5.

Unit Root test: quarterly data, level

Variable	ADF	KPSS	Zivot-Andrews	Remark
Relative price	− 2.14 (− 3.45)	0.194 (0.146)	− 3.64 (− 5.08)	I(1)
Oil price	− 0.705 (− 3.45)	0.212 (0.146)	− 4.61 (− 5.08)	I(1)
Output gap	– 3.22 (− 2.89)	0.056 (0.463)		I(0)
Inflation	− 3.08 (2.89)	0.145 (0.463)		I(0)

Note: Critical values at 5 percent level are given in parentheses. The null hypothesis in the ADF and Zivot and Andrews tests is that the series is I(1) and alternative is that it is I(0). In the KPSS test the null hypothesis I(0) and alternative I(1). In all the cases, the alternative hypothesis is trend stationarity, except in the case inflation, where the plot against time showed no trend and hence the alternative of stationarity around the mean was chosen