A researcher used the Dickey-Fuller method to test for stationarity of four individual countries bond market indices. Monthly total return government bond index data for four countries: Germany, Japan, UK and US for the period January 1978 to April 1990. The results are in the accompanying table

Table 1: DF tests on international bond indices

Country DF Statistic

Germany -0.395

Japan -0.799

UK -0.884

US 0.174

Use DF statistic values to determine whether the individual bond markets are stationary.