Variables

IPS (2003) panel unit root test

Maddala and Wu (1999)

Order of integration

T-bar

W (T-bar)

Total tax to GDP

−1.45

0.11

1.75

I(1)

∆Total tax to GDP

−4.86*

−4.72*

17.2*

Indirect taxes to GDP

−1.22

0.66

−0.24

I(1)

∆Indirect taxes to GDP

−4.12*

−4.32*

10.5*

Direct taxes to GDP

−1.43

0.48

2.11

I(1)

∆Direct taxes to GDP

−5.40*

−5.2*

22.68*

Trade taxes to GDP

−2.69

−2.04

5.33

I(1)

∆Trade taxes to GDP

−5.93*

−5.55*

28.44*

Average Tariff Rate

−2.71

−1.90

3.34

I(1)

∆Average Tariff Rate

−6.15*

−5.28*

13.74*

Agricultural share to GDP

1.30

0.33

0.65

I(1)

∆Agricultural share to GDP

−4.44*

−4.63*

11.71*

GDP per capita

−1.39*

0.27*

20.31*

I(0)

Aid per capita

−5.31*

−4.64*

27.24*

I(0)

Trade ratio

−0.62

2.24

0.02

I(1)

∆Trade ratio

−3.35*

−3.24*

13.04*

Share of urban population to the total population

−1.34

0.80

−0.59

I(1)

∆Share of urban population to the total population

1.36*

0.368*

6.64*

Real effective exchange rate

−1.271

0.543

−0.71*

I(1)

∆Real effective exchange rate

−0.462*

2.669*

−1.94*

Inflation

−4.585*

−3.030*

6.42*

I(0)

Regulatory quality

−5.37*

−5.12*

8.54*

I(0)

Political stability

−6.40*

−4.45*

31.06*

I(0)

Control of corruption

−4.07*

−4.12*

34.43*

I(0)

Accountability

−5.66*

−4.98*

−0.59*

I(0)

Rule of Law

−3.33*

−2.54*

1.19*

I(0)