Two-color printing calculator delivers a valuable combination of useful and sophisticated features for the busy professional. Profit margin calculation keys allow you to calculate the selling price or discount, based on the cost and desired profit margin. The built-in clock and calendar allow you to view the time and date on the display or print them out. Double-check function helps minimize errors for more accurate calculations. Backspace button allows you to quickly correct minor mistakes for time-saving operation. Printing calculator also includes currency conversion, tax calculation, business calculation, sign change, grand total, memory function and more.