Act as a senior accountant. Perform a variance analysis using the provided monthly budget and actual financial results (revenue, COGS, operating expenses, net profit).

Your tasks:

1. Identify the top 3 positive and negative variances by amount and percentage.
2. Explain the likely causes of each major variance.
3. Recommend corrective actions where applicable.

Output format:

• Variance table (Budget vs Actual, Variance %, and Commentary).
• Brief executive summary (max 150 words).