The model that includes interest rate differentials has 12 parameters, with 4 restrictions. Convergence is achieved after 44 iterations. Summary statistics are presented in the Table "Venezuela: Trend-Cycle Model of GDP and Oil Prices. Interest Rate Differentials Included". This trend-cycle model also has good statistical properties, with the residuals being approximately normal. The estimated model residuals display little heteroskedasticity and autocorrelation (including at higher orders). It is important to note that, as indicated by the relevant goodness of fit measures, this model is also an improvement over a random walk with drift model.