Gratuity Calculation & Exit Letter (India)

You are processing gratuity for an employee leaving an Indian company. Two outputs: (1) the calculation, (2) the cover letter.

## Inputs
- Employee name: {{employee_name}}
- Date of joining: {{joining_date}}
- Last working day: {{last_working_day}}
- Last-drawn basic salary per month (₹): {{last_basic}}
- Last-drawn dearness allowance per month (₹): {{last_da}}
- Reason for exit: {{exit_reason}}
- Company name: {{company_name}}
- Bank account for credit (last 4 digits + bank name): {{bank_account}}
- Authorised signatory: {{signatory_name}}, {{signatory_designation}}

## Output 1 — Gratuity Calculation
1. **Eligibility** — confirm completed years of continuous service ≥ 5 (4 years 240+ days counts as 5). Compute years from {{joining_date}} to {{last_working_day}}. If < 5 years AND exit reason is not death/disablement, state "Not eligible for gratuity under Section 4 of the Payment of Gratuity Act, 1972" and stop.
2. **Formula** — (Last basic + DA) × 15 / 26 × number of completed years (any part-year > 6 months rounds up).
3. **Computed gratuity** — show the math.
4. **Statutory cap** — ₹20 lakh is the lifetime cap on tax-exempt gratuity under Section 10(10) of the IT Act. Anything above is taxable.
5. **Tax treatment** — exempt up to the lower of (formula amount / ₹20L / actual received).

## Output 2 — Cover Letter
- Date.
- To: {{employee_name}}.
- Subject: "Final Settlement — Gratuity under Payment of Gratuity Act, 1972".
- Body 3 paragraphs:
  1. Acknowledge service from {{joining_date}} to {{last_working_day}}, total completed years.
  2. State gratuity amount and calculation reference (Section 4 of the Act).
  3. Confirm credit to {{bank_account}} within 30 days (statutory timeline under Section 7(3)).
- Sign-off: {{signatory_name}}, {{signatory_designation}}, {{company_name}}.

Neutral tone. No congratulations or farewell prose — keep that for a separate letter.