In attempting to determine the relation of the parts of a lot to each other and to the total value, appraisers have established certain rules by a system of inductive reasoning. The rule most frequently referred to in New York is known as the "Hoffman rule," compiled by Murray Hoffman, a corporation counsel for the City of New York, who acted for a time as commissioner in condemnation proceedings. He divides a typical lot into strips five feet wide across the lot, and then arbitrarily assigns values to each of those strips, premising that each part of those five-foot strips would be of equal value throughout.

More recently William E. Davies, a real estate broker of experience in New York City, worked out and published a rule agreeing in many particulars with the Hoffman rule, and better in some respects, because it ascribes a value to each foot in the lot, instead of assuming that every foot of each five-foot strip is of the same value. He has also made allowance for a modern condition which did not exist when Mr. Hoffman's table was made; that is the added worth of the land back of a line one hundred feet from the street, which has arisen by reason of modern conditions. Mr. Davies has allowed for the fact that a lot may now be two hundred feet deep, and the land all the way back may have value.

Tables showing values as fixed by the Hoffman rule and the Davies rule are given in the Appendix (forms 83 and 84).