Papertape Calculator 2.1 is a full function calculator that records all entries to a virtual paper tape (text file). It simplifies checking of one's work and allows multiple results to be displayed simultaneously. It Includes user defined functionality as well as binary, octal and hexadecimal arithmetic and importation and calculation of external data sets that include curve fits. Business functions include interest, annuity and loan calculations. Math functions include trigonometry, statistics, regression analysis, quadratic and cubic equations. The software also includes conversion factors and area under curve calculations (numerical integration). Ten memory locations store numbers and text together.

New features of Papertape Calculator 2.10 include:

• Calculation of net present value of cash flow.
• Calculation of bond prices.
• Calculation of four versions of depreciation.
• Added calandar functions include; the determination of the number of days between dates; the date determined from the number of future days; the day of the week from the date and the number of days gone in the year.
• Matrix algebra.
• Normalization factor, with user defined exponent, added to determination of curve fits.
• Trigonometric functions, Conversions and Constants now more accessible from a menu on the "equations" menu.
• Prime factorization of integers available.
• All default files saved to directory of executable files. (See readme.)
• Limits on number of data points enterable for all functions have been lifted.
• Memory demands on computer have been reduced.
• Scientific notation excluded from all business calculations.
• Reload of memory for continuing equations repaired.

Improvements in Papertape Calculator included in earlier versions include:

• User defined functions can be entered and solved. Instead of inputing an experession with keystrokes or button clicking, following input of a colon (:), a mathematical expression can be typed in that will be solved all at once. If the expression contains the variables 'x' or 'y' at any location in the equation, and any number of times, the calculator will prompt the user for values of these variables and solve the equation. This action is repeatable.
• External data sets can be input to be solved by the available calculator functionality.
• Curve fits of user defined or stored functions can be made to external data sets input to the calculator.
• Areas under sections of a bell curve, parabola or user defined function can be determined by numerical integration.
• Binary, octal and hexadecimal arithmetic functions are color coded for easier use.
• Archive is time stamped when calculator is opened to create a clearer record of calculator usage.
• Keyboard entry for most functionality.
• Multi-function calculator that allows for running calculations.
• Papertape records all data entries and operations as well as multiple results in calculations. Text entry to papertape is also possible. All data entries and operations are archived.
• Data entered can be saved for later use.
• Displayed papertape can be saved for user's records or recalled to calculator.
• Individual numerical entries on the papertape or archive can be double clicked to the display for further use in calculations.
• Parenthesis function allow for user control of order of operation execution.
• Compound interest calculations.
• Simplified linear least squares regression analysis.
• Simplified multiple regression analysis which allows use of dummy variable.
• Trigonometric functions.
• Conversion calculations.
• Constants.
• 10 memory locations. Window displays memory contents.
• Currency format for basic functions.
• Detailed instructions and documentation.
• Constant key functionality available.
• Percent calculations.
• Calculation of y values on lines and planes.
• Quadratic and Cubic equations.
• Bessel Functions.
• Loan (home mortgage) and amortization calculations.
• Annuity calculations.
• Statistics for grouped data.
• Area under a section of a parabola or normal "bell" curve can be calculated.
• Calculation of Ideal Gas Law now available.
• Arithmetic using Binary, Octal and Hexadecimal bases.