Variable

Level

First difference

ADF

PP

ADF

PP

GDP

−3.702**

−3.425**

−5.542*

−5.591*

K

−1.412

−1.523

−3.896**

−3.974**

L

−2.892

−2.964

−5.313*

−4.564*

E

−1.759

−1.421

−7.041*

−7.241*