Tests of cointegrating rank with a trend-break

The conventional testing procedure may mislead one into accepting the null of no cointegration or the null of a cointegrating rank smaller than the true rank when there is a trend-break under the alternative hypothesis. This paper proposes tests for cointegrating rank that have power against the trend-break alternative. The proposed tests are applied to the US money demand function. The results support the Campbell–Perron conjecture: money, income and interest rates are cointegrated around a broken trend.