Seasonal Kendall Test for Trend US Geological Survey, 2005 Data set: Example SK1c - Seasonal Kendall test, input type 1 The record is 7 complete water years with 12 seasons per year beginning in water year 1975. The tau correlation coefficient is -0.063 S = -12. z = -0.584 p = 0.5592 p = 0.2838 adjusted for correlation among seasons (such as serial dependence) The adjusted p-value should be used only for data with more than 10 annual values per season. The estimated trend may be described by the equation: Y = 0.6000E-01 + 0.000 * Time where Time = Year (as a decimal) - 1974.75 (beginning of first water year)