year (including extensions thereof). The method so elected, and the period selected by the taxpayer, shall be adhered to in computing taxable income for the taxable year for which the election is made and for all subsequent taxable years unless, with the approval of the Secretary, a change to a different method (or to a different period) is authorized with respect to part or all of such expenditures. The election shall not apply to any expenditure paid or incurred during any taxable year before the taxable year for which the taxpayer makes the election. (c) Land and Other Property This section shall not apply to any expenditure for the acquisition or improvement of land, or for the acquisition or improvement of property to be used in connection with the research or experimentation and of a character which is subject to the allowance under section 167 (relating to allowance for depreciation, etc.) or section 611 (relating to allowance for depletion)