Wagner's Law in Sri Lanka: An Econometric Analysis

Table 3

ADF and PP unit root test.

Variables	Augmented dickey fuller (ADF)		Phillip Perron (PP)		Decision (order of integration)
	Level	First difference	Level	First difference
GDP	−1.192	−11.721*	−2.752	−16.827*	I(1)
NEXP	−1.612	−5.161**	−1.336	−2.612**	I(1)
RPCEXP	0.835	−5.937*	0.657	−5.937*	I(1)
REXP	0.952	−5.848*	0.766	−5.847*	I(1)
RGDP	−1.612	−2.626**	0.762	−6.681*	I(1)
RPCGDP	−1.612	−2.625**	0.613	−6.818*	I(1)

*, **,** are significant at one percent, five percent and ten percent level.
GDP: gross domestic product, NEXP: nominal expenditure, RPCEXP: real per-capita expenditure, REXP: real expenditure, RGDP: real GDP, RPCGDP: real per-capita GDP.