You have a $45M annual marketing budget.

You have a $45M annual marketing budget. You allocate it based on last year's performance. Your CAC has risen 26% in 6 months. A CFO at a $300M retailer told me: *"We approve the marketing budget every year. We have no idea if it's the right allocation. We just know it's what we spent last year."* That's not budgeting. That's autopilot. When I took over a $45M budget operation, allocation was legacy-based. Channels that performed well in 2019 got more budget in 2023, regardless of current performance. We rebuilt the entire budgeting model around real-time ROI. Profit grew 47% while spend grew only 12%. **The Dynamic Budgeting Framework:** 1. Budget is fluid, not fixed. We reallocate 15% of budget monthly based on performance.n2. Test small, scale big. Every new channel starts with 1% of budget. Prove or kill quickly.n3. Build budget buffers. We hold 10% of budget for opportunistic moves and experiments.n4. ROI thresholds by channel. Facebook needs 300% ROI. Retail media needs 200%. Every channel has its own math.n5. Scenario planning. We model recession, growth, and flat scenarios. We're ready for anything. The brands thriving in 2026 aren't managing static budgets. They're managing dynamic capital allocation. I've cut CPA by 66%, lifted ROAS by 67%, and enabled a £790M IPO. But the breakthrough came when we stopped budgeting on autopilot. How do you allocate your marketing budget? Data or tradition?