What is the Fast FormulaReturn Value needed for Effective Date Column in Workforce Compensation Plan

Summary:

Hi, I've been trying to figure out what is the valid return value for the Effective Date column. I've done many trial and error but still can't manage to display the return value. Please advise

Note: there is no error in compiling, the error shows on the tester.

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Code Snippet (add any code snippets that support your topic, if applicable):

L_PERSON_ID = get_context(person_id, -1)

L_DEFAULT_VALUE='1951/01/01'(date)

l_temp_value=' '

l_person_id_char=TO_CHAR(L_PERSON_ID)