* Additional unit tests and rationalisation for Financial Functions
* Providing a series of sample files for Financial functions
* Refactor the last of the existing Financial functions
* Some more unit tests with default assignments from null arguments
Co-authored-by: Adrien Crivelli <adrien.crivelli@gmail.com>
* First steps splitting out the Amortization and Deprecation Excel functions from Financials
* Verify which methods allow negative values for arguments
* Additional unit tests for SLN() and SYD()
* Additional unit tests for DDB()
* Additional unit tests for DB()
* Verify Amortization cases where salvage is greater than cost
* More unit tests for Amortization
* Resolve broken test in AMORLINC() and extract amortizationCoefficient calculation
* verify amortizationCoefficient calculation
* Extract YIELDDISC() and YIELDMAT() to Financial\Securities
* Additional validation for Securities Yield functions
* Additional unit tests for previously untested financial functions, and some additions to follow untested paths
* Start splitting Financial function tests out from the large FinancialTests class into individual test classes for each function