(a) As used in this Code section, the term:

(1) "Base amount" means the product of a business enterprise's Georgia taxable net income in the current taxable year and the average of the ratios of its aggregate qualified research expenses to Georgia taxable net income for the preceding three taxable years or 0.300, whichever is less.

(2) "Business enterprise" means any business or the headquarters of any such business which is engaged in manufacturing, warehousing and distribution, processing, telecommunications, tourism, and research and development industries. Such term shall not include retail businesses.

(3) "Qualified research expenses" means qualified research expenses for any business enterprise as that term is defined in Section 41 of the Internal Revenue Code of 1986, as amended, except that all wages paid and all purchases of services and supplies must be for research conducted within the State of Georgia.

(b) A tax credit is allowed a business enterprise which has qualified research expenses in Georgia in a taxable year exceeding a base amount, provided that the business enterprise for the same taxable year claims and is allowed a research credit under Section 41 of the Internal Revenue Code of 1986, as amended.

(c) The tax credit provided in subsection (b) of this Code section shall be 10 percent of the excess over the base amount referred to in said subsection.

(d) Any unused credit claimed under this Code section may be carried forward ten years from the close of the taxable year in which the qualified research expenses were made. The credit taken in any one taxable year shall not exceed 50 percent of the business enterprise's remaining Georgia net income tax liability after all other credits have been applied.