To the Honorable Senate:

The undersignéd justices of the supreme court return the following reply to the inquiries contained in your resolution adopted April 8, 1975, and filed with this court on April 11, 1975.

Economic legislation, like the regulation of finance charges, to be constitutional must be based on some substantial and rational foundation. Valley Bank v. State, 115 N.H. 151, 335 A.2d 652 (1975); Granite State Grocers Ass’n v. State Liquor Comm’n, 112 N.H. 62, 66, 289 A.2d 399, 402 (1972); Welch Co. v. State, 89 N.H. 428, 432, 199 A. 886, 888 (1938), aff'd, 306 U.S. 79 (1939). Classifications, therefore, made by such legislation must reasonably promote some proper object of public welfare or interest. Welch Co. v. State supra; Marine Corps League v. Benoit, 96 N.H. 423, 427, 78 A.2d 513, 517 (1951).

*221Here the proposed statute would amend RSA ch. 399-B, which is concerned with the disclosure of finance charges. See Annot., 14 A.L.R.3d 330 (1967, Supp. 1974). By adding the proviso contained within House bill No. 253, the State would not only require disclosure of credit charges but would limit the interest chargeable on only certain types of credit cards. The amendment would specifically limit interest chargeable on sales of “gasoline and related products and for primarily personal, family or household purposes ....” made on credit cards “issued by a manufacturer or distributor of gasoline and related products [to] three-quarters of one per cent per month on the unpaid balance.” Hence, manufacturers and distributors of gasoline and related products are singled out for reg ulation while others issuing credit cards are not regulated by the proposed act.

We are of the opinion that the proposed House bill No. 253 is unconstitutional, because it arbitrarily discriminates against a certain category of credit card issuers. See Rosenblum v. Griffin, 89 N.H. 314, 197 A. 701 (1938); N.H. Const. pt. I, art. 12.

April 30, 1975