Discussion of “Innovative approaches to the trend assessment of streamflows in the Eastern Black Sea basin,Turkey”^*

The research paper by Akçay et al. applied innovative polygon trend analysis (IPTA) to derive trend length/volume and trend slope between two consecutive months for rainfall/streamflow in the eastern Black Sea basin, Turkey. Although the trend length/volume equation is correct, the trend slope equation is fundamentally incorrect. A brief discussion is presented to apprise the research community of the correct trend slope equation.