Hewlett-Packard may be spinning off its PC business, but the company is still making calculators for accountants and other folks.

On Tuesday evening, the company marked the 30th anniversary of one of its most popular models, the HP 12c financial calculator, with a reception in New York. The company has continued making the calculator after all these years, albeit with newer hardware inside. Gene Wright of Lipscomb University, who literally wrote the book on HP calculators, still runs his formulas on HP calculators. His manual, “Quantitative Analysis for Business,” is now in its third edition.

HP is introducing a limited edition 30th anniversary of the HP 12c calculator, complete with a gift box, on Thursday. The Palo Alto, Calif.-based tech giant is also bringing back the HP 15c scientific calculator, which it discontinued in 1989, to mark its 29th anniversary as well. Good thing they’re not running the webOS software that HP acquired when it bought Palm last year, which now has an uncertain future along with HP’s PC and tablet business. At least the calculators have endured.