Gabaɗaya, idan muka yi magana da index na guduro ruwan tabarau, yana daga 1.49 – 1.56 – 1.61 – 1.67 – 1.71 – 1.74. Don haka ƙarfin guda ɗaya, 1.74 shine mafi ƙarancin ƙarfi, mafi girman ƙarfin, mafi kyawun tasirin tasirin.