B. For the purposes of this section:

1. 1. Except as provided in paragraph 2 of this subsection, depreciation shall be computed on a straight-line basis using the lives set forth as follows:

   1. (a) Buildings with a twenty-five-year life.
   2. (b) Cable with a fifteen-year life.
   3. (c) Telecommunications equipment with a five-year life.
   4. (d) Any other telecommunications property that is not included in subdivisions (a), (b) and (c) of this paragraph with a seven-year life.

2. 2. For qualifying broadband infrastructure, depreciation shall be computed as follows:

   1. (a) Cable shall be computed on a straight-line basis using a ten-year life.
   2. (b) Telecommunications equipment shall be computed on a straight-line basis using a five-year life.
   3. (c) Any other telecommunications property that is not included in subdivisions (a) and (b) of this paragraph shall be computed on a straight-line basis using a seven-year life.

   4. (d) Additional depreciation shall be applied to personal property as follows:

      1. (i) For the first tax year of assessment, the department shall use twenty-five percent of the scheduled depreciation value.
      2. (ii) For the second tax year of assessment, the department shall use forty-one percent of the scheduled depreciation value.
      3. (iii) For the third tax year of assessment, the department shall use fifty-seven percent of the scheduled depreciation value.
      4. (iv) For the fourth tax year of assessment, the department shall use seventy-three percent of the scheduled depreciation value.
      5. (v) For the fifth tax year of assessment, the department shall use eighty-nine percent of the scheduled depreciation value.
      6. (vi) For the sixth tax year of assessment and each subsequent tax year of assessment thereafter, the department shall use the scheduled depreciation value.
   5. (e) The computation prescribed in this paragraph shall not reduce the valuation of property valued pursuant to subdivision (a) of this paragraph below two and one-half percent of the cost and shall not reduce the valuation of property valued pursuant to subdivisions (b), (c) and (d) of this paragraph below two and one-half percent of cost.
3. 3. The computation prescribed in paragraph 1 of this subsection shall not reduce the valuation of property valued pursuant to paragraph 1, subdivision (a) of this subsection below twenty percent of cost and shall not reduce the valuation of property valued pursuant to paragraph 1, subdivisions (b), (c) and (d) of this subsection below ten percent of cost.
4. 4. For cellular or other wireless telecommunications companies, the taxable unit is the applicable metropolitan statistical area or rural statistical area and does not include the value of any license that is issued by the federal communications commission.

C. For the purposes of this section:

1. 1. "Cost" means the original cost as reported on the company's books and records.
2. 2. "Obsolescence" means a reduction in the value of an asset resulting from functional or economic obsolescence.
3. 3. "Qualifying broadband infrastructure" means cable, telecommunications equipment and other tangible personal property capable of being used for or in connection with the transmission of data at a rate that is at least equal to four megabits per second in at least one direction, including multiplexers, routers, servers, fiber optics, coaxial cable and equipment supporting the transmission function first placed in service on or after January 1, 2017.