| ADF tests | PP tests | |||
| Variables at level | Model with tendency | |||
| 5% significance | ||||
| t-statistic | P-value (%) | t-statistic | P-value (%) | |
| y Xp Xph Xpo Xm Xa | −3.658 −3.658 −3.733 −3.733 −3.658 −3.691 | 20.1 72.65 26.25 42.37 56.6 99.84 | −3.658 −3.661 −3.658 −3.658 −3.658 −3.658 | 2.06 72.64 78.57 100 56.66 99.98 |