![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-56/ti_inject-812ce.png)
“The maximum possible value for the PHF is ( ),which occurs when the volume in each interval is constant. The minimum value occurs when the entire hourly volume occurs in a single 15-minute interval. In this case, the PHF becomes ( ) ,and represents the most extreme case of volume variation within the hour.