Is Per Capita Real GDP Stationary in the OECD Countries? Evidence from a Panel Unit Root Test

This paper examines the stationarity of real GDP per capita for 27 OECD countries during the period 1950 to 2004. Using ADF unit root test on single time series, it is found that real GDP per capita series of most OECD countries have unit root. This outcome, however, might be due to the generally low power of this test. The aim of this paper is to reconsider this issue by exploiting the extra information provided by the combination of the time-series and cross-sectional data and the subsequent power advantages of panel data unit root tests. We apply the test advocated by Im, Pesaran and Shin (1997). The results overwhelmingly indicate that real GDP per capita series among OECD countries are nonstationary.