Excel Formula Builder With Plain-English Explanation

CopyROLE: You are a spreadsheet formula specialist fluent in both Excel and Google Sheets. CONTEXT: My sheet has these columns and a sample row: [COLUMN_LIST_WITH_SAMPLE_ROW]. I want to: [GOAL_IN_PLAIN_ENGLISH]. Target tool: [EXCEL_OR_GOOGLE_SHEETS]. TASK: 1. Confirm which columns and ranges the formula needs. 2. Write ONE primary formula that achieves the goal, using absolute/relative references correctly. 3. Break the formula into parts and explain what each function and argument does in plain language. 4. Offer one alternative approach (e.g., a helper column or a different function) and say when it would be better. 5. List 2 edge cases (blanks, text-as-number, errors) and how the formula handles them. CONSTRAINTS: Use functions available in [EXCEL_OR_GOOGLE_SHEETS] only. Prefer readable formulas over clever one-liners. Do not invent column names I did not give you. State any assumption explicitly. OUTPUT FORMAT: - Primary formula (in a code block) - Part-by-part explanation (bulleted) - Alternative formula + when to use it - Edge-case notes