Further evidence regarding nonlinear trend reversion of real GDP and the CPI

his paper examines whether the CPI and real GDP for the U.S. exhibit nonlinear reversion to trend as recently concluded by Beechey and Österholm [Beechey, M. and Österholm, P., 2008. Revisiting the uncertain unit root in GDP and CPI: testing for non-linear trend reversion. Economics Letters 100, 221-223]. The wild bootstrap is used to correct for non-normality and heteroscedasticity in a nonlinear unit root test. Test results are found to be sensitive to the sample period examined.