The plane coordinate values for a point on the earth's surface, used to express the horizontal position or location of such point on the Vermont Coordinate Systems, shall consist of two distances, expressed in U.S. Survey feet and decimals of a foot when using the Vermont Coordinate System 1927 and expressed in meters and decimals of a meter, or U.S. Survey feet and decimals of a foot when using the Vermont Coordinate System 1983. One of these distances, to be known as the "x-coordinate," shall give the position in an east-and-west direction; the other, to be known as the "y-coordinate," shall give the position in a north-and-south direction. These coordinates shall be made to depend upon and conform to plane rectangular coordinate values for the monumented points of the National Spatial Reference System established by the U. S. Coast and Geodetic Survey, its predecessor, or its successors. (Amended 1987, No. 169 (Adj. Sess.), § 2, eff. May 3, 1988; 2007, No. 164 (Adj. Sess.), § 39.)