Comprehensive and Detailed 150 to 250 words of Explanation From Workday Record-to-Report/Course Guide/topics:

Company Currency becomes immutable once a financial transaction exists for the company. It is a foundational accounting attribute used to store ledger amounts, convert transaction currencies, calculate balances, and produce the company's statutory financial statements. Changing it after activity has been recorded would invalidate historical conversion results and undermine the continuity of ledger balances.

Workday applies similar protection to other core company accounting attributes, including the fiscal schedule and account set, but among the choices presented Company Currency is the applicable locked detail. Account Translation Rule Sets govern how balances are translated into reporting currencies and may be maintained as reporting requirements evolve. Account Posting Rule Sets determine the ledger accounts generated from operational transactions, while Account Control Rule Sets impose journal controls; neither is the company's immutable base-currency identity. Administrators must therefore complete currency design and legacy-data planning before creating the first financial transaction. If the legal entity requires reporting in another currency, Workday uses translation rules and reporting currencies rather than altering the established company currency. This preserves the original accounting basis and provides a consistent audit trail across all operational and accounting journals.

Official Workday reference: Workday Education - Financial Accounting Setup ; topics: Edit Company Accounting Details and locked company currency.

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