Augmented Dickey-Fuller test for unit root Number of obs = 430 Interpolated Dickey-Fuller Test 1% Critical 5% Critical 10% Critical Statistic Value Value Value Z(t) -1.045 -3.446 -2.873 -2.570 MacKinnon approximate p-value for Z(t) = 0.7366 Hurn (NCER) Applied Financial Econometrics using Stata 18 / 42 kpss performs the Kwiatkowski, Phillips, Schmidt, Shin (KPSS, 1992) test for stationarity of a time series. This test differs from those in common use (such as dfuller and pperron) by having a null hypothesis of stationarity. The test may be conducted under the null of either trend stationarity (the default) or level stationarity. Inference from this test is complementary to that derived from