[Gretl-users] VECM and IRF interpretation

Hi! I have a question regarding VECM and IRF interpretation in Gretl. According to the speed of adjustment coefficient in the VEC, the target variable adjusts at a speed of 15,5% per year to equilibrium. But the IRF says that the cumulative change in the target variable is only 2% from year four trough the time horizon of the IRF, which is nine years. How can I interpret this? Best regards, Lars