Chart Type for Funnel / Flow. Keywords: funnel, flow, conversion, drop-off, pipeline, stages. Best Chart: Funnel Chart or Sankey. Secondary Options: Waterfall (for flows). When to Use: Sequential multi-stage process; showing conversion or drop-off rates between defined stages. When NOT to Use: Stages aren't sequential; values don't decrease monotonically (use bar); fewer than 3 stages. Data Volume Threshold: 3–8 stages optimal; beyond 8 stages group minor steps into 'Other'. Color Guidance: Stages: single color gradient (start → end). Show conversion % between each stage. Highlight biggest drop. Accessibility: AA — Explicit conversion % as text per stage. Stage labels always visible. Linear list view as fallback.. A11y Fallback: Provide linear list view with stage name + count + drop-off %; keyboard traversal. Library: D3.js, Recharts, Custom SVG. Interactive Level: Hover + Drill.