12-digit calculator prints 3.7 lines per second in two colors with positive numbers in black and negative numbers in red. Features cost-sell-margin; profit margin; quick tax calculation; calendar and clock on display; grand total; decimal positions in +, 0, 2, 3, 4, 6, floating; non-add print; round-up/off/down; item count; sign change, grand total; and oversize plus, minus and total keys.