State the ratio of rainfall and evaporation

The ratio of rainfall and evaporation is called as P/E ratio, where P stands for precipitation and E for evaporation. If P/E ratio is large the weathering will be quick.  If P/E ratio is less weathering will be slow.  In combination with other factors rainfall also determines the depth of water table and in long run would affect the capillary movement of water and aeration. Rainfall influences soil formation indirectly through the activities of plant and animal life.  The nature, type and amount of vegetation which it supports in turn modify the effects of rainfall.