Efficiency (\( E_d = 100 \left[1 - \left(\frac{y}{d}\right)\right] \)):

Where:

• \( E_d \) is the water distribution efficiency, expressed as a percentage.
• \( y \) is the average numerical deviation in depth of water stored from the average depth stored during irrigation, in meters.
• \( d \) is the average depth of water stored during irrigation, in meters.