(1)When assessing rent under section 157 for the assessable area of Chahi (well irrigated) holding in the manner specified in sections 159 to 162, regard shall also be had to the areas thereof cultivated as Chahi, cultivated as dry and kept fallow each year and such rent shall be the aggregate of the rents calculated in respect of the average of the areas of the holding cultivated Chahi, cultivated as dry and kept fallow during the last five years at the appropriate sanctioned rent-rates respectively for Chahi, dry and fallow lands.