Floor Area Ratio (FAR) is the fundamental metric used to measure the density of a development. It is determined by dividing the total building floor area by the area of its zoning lot (ie. the land it sits on). Each type of zoning district in the city has a maximum allowable FAR, and the higher the number, the greater the possible density. Most rezonings involve changing the allowable FAR, to either increase or decrease the permitted density. Many zoning districts do not restrict height, but all have a maximum allowable FAR.