In In re Young, 911 A.2d 605, 608-9 (Pa. Cmwlth. 2006) this Court stated: It is generally acknowledged that, once a value has been established for a taxable property, that value cannot be changed absent one of the following circumstances: (1) undertaking of a county-wide reassessment; (2) appeal of property assessment by either the landowner pursuant to section 701 of the Assessment Law, 72 P.S. 5453.701, or by the taxing authority under section 706 of the Assessment Law, 72 P.S. 5453.706; (3) need for a downward adjustment is necessary under section 703.3 of the Assessment Law, added by section 2 of the Act of September 28, 1965, P.L. 550, as amended, 72 P.S. 5453.703c; (4) need to correct a mathematical or clerical error; or; (5) presence of one of the three conditions outlined in section 602.1 of the Assessment Law, 72 P.S. 5453.602a. When none of these circumstances exists, a taxing authority's reassessment of property constitutes an impermissible spot reassessment.