Dates Form Calculator

Introduction

This calculator will calculate the following date calculations that are commonly required in finance and accounting. It can compute:

• Actual Days Between Two Dates: The real number of days between any two given dates.
• 30/360 Basis (NASD) Days Between Two Dates: The number of days between two dates based on the 30/360 day count convention, following the National Association of Securities Dealers (NASD) standards.
• 30E/360 Basis (European) Days Between Two Dates: The number of days between two dates based on the 30E/360 European day count convention.
• Calculate a Date by Adding Actual Days: Determine a future or past date by adding a specified number of actual days to a given date.

Using the Calculator

• To calculate any of the above values, tap the "=" button to the left of the value you wish to calculate.
• Select a date by tapping the blue date buttons. This action opens an iOS date picker for easy and accurate date selection.
• After making any change, the actual days input box will turn gray to indicate that a calculation is pending. The 360 and 360E values will be marked with an asterisk (*) to denote that they are pending calculation.
• Only the actual days between value can be manually entered. This input is used to calculate either the start or end date based on the calculation type selected.
• To calculate values for the 360 days between, the Start Date must be before the End Date. Some other calculators and spreadsheets will return negative days when the start date is after the end date, but these values can be incorrect. The standards are based on the start date being before the end date and adjust the days of the month differently for the start and end dates. For example, 8/15 to 12/31 is 136 days but 12/31 to 8/15 is -135 days. So you cannot use a negative number.
• The "=" button's functionality is context-sensitive. It determines which value will be returned from the History List for use in calculations or for reference.

Standards and Testing

The calculator uses the Standard Securities Calculation Methods as noted in the reference for 30/360 calculations. This ensures compliance with recognized financial calculation standards.

Apple Numbers has been utilized for test cases to verify the accuracy of the NASD and European day count convention calculations. This aligns the calculator's performance with established software standards, as noted in the reference.

Reference

The calculator's day count conventions are based on the principles outlined in the 360-day calendar Wikipedia page.