A. Except as provided in subsection B of this section, the taxpayer shall elect to apportion all business income to this state for taxable years beginning from and after:

1. 1. December 31, 2006 through December 31, 2007 by either:

   1. (a) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four.
   2. (b) Multiplying the income by a fraction, the numerator of which is two times the property factor plus two times the payroll factor plus six times the sales factor, and the denominator of which is ten.

2. 2. December 31, 2007 through December 31, 2008 by either:

   1. (a) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four.
   2. (b) Multiplying the income by a fraction, the numerator of which is one and one-half times the property factor plus one and one-half times the payroll factor plus seven times the sales factor, and the denominator of which is ten.

3. 3. December 31, 2008 through December 31, 2013 by either:

   1. (a) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four.
   2. (b) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus eight times the sales factor, and the denominator of which is ten.

4. 4. December 31, 2013 through December 31, 2014 by either:

   1. (a) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four.
   2. (b) Multiplying the income by a fraction, the numerator of which is seven and one-half times the property factor plus seven and one-half times the payroll factor plus eighty-five times the sales factor, and the denominator of which is one hundred.

5. 5. December 31, 2014 through December 31, 2015 by either:

   1. (a) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four.
   2. (b) Multiplying the income by a fraction, the numerator of which is five times the property factor plus five times the payroll factor plus ninety times the sales factor, and the denominator of which is one hundred.

6. 6. December 31, 2015 through December 31, 2016 by either:

   1. (a) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four.
   2. (b) Multiplying the income by a fraction, the numerator of which is two and one-half times the property factor plus two and one-half times the payroll factor plus ninety-five times the sales factor, and the denominator of which is one hundred.

7. 7. December 31, 2016 by either:

   1. (a) Multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four.
   2. (b) Multiplying the income by the sales factor.

B. All business income of a taxpayer engaged in air commerce shall be apportioned to this state by multiplying the income by a fraction, the numerator of which is the revenue aircraft miles flown within this state for flights beginning or ending in this state and the denominator of which is the total revenue aircraft miles flown by the taxpayer's aircraft everywhere. This subsection applies to each taxpayer, including a combined group filing a combined return or an affiliated group electing to file a consolidated return under section 43-947, if fifty per cent or more of that taxpayer's gross income is derived from air commerce. For the purposes of this subsection:

1. 1. "Air commerce" means transporting persons or property for hire by aircraft in interstate, intrastate or international transportation.
2. 2. "Revenue aircraft miles flown" has the same meaning prescribed by the United States department of transportation uniform system of accounts and reports for large certificated air carriers (14 Code of Federal Regulations part 241).