Abstract: The specification discloses a handheld computing device or portable electronic calculator that comprises a software application adapted to provide instructions to perform math operations to calculate trading and investment variables and display these variables resulting from the math operation(s) on the display screen simultaneously along with descriptive acronyms. The software application may be further adapted to provide instructions that allows a user to input trading and investment variables including trading price/or trading premium and then incrementing trading price/or premium by decimal or fraction with up and down arrow key(s) or “speed key(s)” on the input device concurrently while viewing the trading price/or premium and calculated order size/or number of contract(s) changes on the display screen.

Abstract: The specification discloses a handheld computing device or portable electronic calculator that comprises a software application adapted to provide instructions to perform math operations to calculate trading and investment variables and display these variables resulting from the math operation(s) on the display screen simultaneously along with descriptive acronyms. The software application may be further adapted to provide instructions that allows a user to input trading and investment variables including trading price/or trading premium and then incrementing trading price/or premium by decimal or fraction with up and down arrow key(s) or “speed key(s)” on the input device concurrently while viewing the trading price/or premium and calculated order size/or number of contract(s) changes on the display screen. The handheld computing device or portable electronic calculator determines variables that are used during active trading and investment (e.g.

Abstract: The specification discloses a hand-held electronic calculator for use by traders for rapidly and easily determining trade order size(s), number of option(s) or contract(s), and other unknown/or not stored variables for an option(s) trade, and a variety of margin, percentage, cash flow, and rate-of-return calculations. These “hand-held” electronic calculators for trading have a variety of product lines and models (e.g. pocket, hand-held, and desktop) and will be for “traders of all levels . . . trading securities of all types”. These innovative hand-held calculators allow traders worldwide to be fast, proactive, prepared, and informed . . . enabling them to increase productivity and profits. Trade order sizes can be determined for stocks, options, bonds, mutual funds, futures, indexes, currency, commodities, or any other security in the world that is traded using price and buying power as variables to compute trade order size.