According to the New Theory, the average family's 15 rai of land will be divided into four parts in a ratio of 30:30:30:10. The first 30 percent, or 4.5 rai, is meant for a pond to support cultivation. A pond about four meters deep holds up to 19,000 cubic meters of rainwater, for the whole year's crop cultivation. The pond may also bring in additional income from aquatic animals and plants.