What is the test for determining the value of a parcel of land which is subject to condemnation action?

'It is the law, as stated by appellant, that in arriving at a determination of the market value of land which is the subject of a condemnation action, it is not proper to consider the increase, if any, in the value of such land by reason of the proposed improvement which is to be made on the land by the condemnor. (See San Diego Land etc. Co. v. Neale, 78 Cal. 63, 75, 20 P. 372, 3 L.R.A. 83; United States v. Miller, 317 U.S. 369, 63 S.Ct. 276, 87 L.Ed. 336, 345, 147 A.L.R. 55.)'