{"id":"fpa-channel-cac-payback-ranking","audience":"fpa","category":"finance-work","track":"finance","technique":"format","level":"intermediate","title":"Rank acquisition channels by payback months","free":false,"task":"You're ranking acquisition channels for the marketing review. Write a prompt for a markdown table with columns Channel | Spend | Customers | CAC | Payback (months), one row per channel sorted by payback from shortest to longest. CAC = spend / customers. Payback = CAC / monthly gross profit per customer. Facts only: don't comment on brand value or recommend a channel. No commentary. Under 90 words.","materialLabel":"Channel spend, customers and unit gross profit (attached to your prompt automatically)","material":"CHANNEL EFFICIENCY - Q3 2026, Brightpath Learning\n\nChannel | Spend | New customers\nPaid search | $60,000 | 40\nEvents | $45,000 | 10\nReferrals | $12,000 | 12\n\nMonthly gross profit per customer (all channels): $500.\nFormulas: CAC = spend / new customers. Payback in months = CAC / monthly gross profit per customer.\n\nNotes: the events lead says events 'build brand' and should be judged differently. That argument isn't part of this table. Referral spend is the referral bonus paid to existing customers.","rules":[{"type":"maxWords","max":90},{"type":"maxBullets","max":0}],"promptHints":[{"label":"Names the columns","patterns":["channel.*spend.*customers.*cac.*payback","columns"]},{"label":"Gives the formulas","patterns":["spend / (new )?customers","cac / "]},{"label":"Asks for sorting","patterns":["sorted","shortest to longest"]},{"label":"Bans commentary","patterns":["no (other )?commentary","brand"]},{"label":"Limits output","patterns":["only the table"]}],"mistakes":[{"title":"Not sorting","why":"The AI keeps the original order.","fix":"Say: \"Sort from shortest to longest payback.\"","checks":["r2"]},{"title":"Payback from revenue or spend","why":"The AI divides spend by $500 or by customers.","fix":"Add: \"Payback = CAC / $500.\"","checks":["r1"]},{"title":"Adding brand commentary","why":"The AI notes events build brand and suggests a different measure.","fix":"Add: \"No comments about brand value and no recommendations.\"","checks":["r2"]},{"title":"Wrong columns","why":"The AI adds a gross profit column or drops CAC.","fix":"Say: \"Columns exactly: Channel | Spend | Customers | CAC | Payback (months).\"","checks":["r0","maxBullets"]},{"title":"Trusting the AI to count words","why":"AI is bad at counting and runs past word limits.","fix":"Ask for fewer words than the real cap and keep each line short.","checks":["maxWords"]}],"hint":"A ranking needs a formula, a sort and no side arguments. Give all three.","rubricLabels":["Table has the columns Channel | Spend | Customers | CAC | Payback (months) with three rows","CAC values are $1,000 (Referrals), $1,500 (Paid search) and $4,500 (Events)","Rows are sorted by payback 2.0, 3.0, 9.0 months (Referrals, Paid search, Events) and the output has no commentary about brand value or recommendations"]}