Playbooks · TV budgeting
Convert a 15-second spot's cost to its 30-second equivalent
This job converts a seller's quote for a 15-second spot into its cost-per-point on a 30-second basis, so it can sit next to 30" rates in the same comparison. It feeds the decision to accept, negotiate down, or reject the 15" quote against the standing 30" benchmark.
What you need first
- Seller's rate quote for the 15" spot: price and the wTRP it is booked to deliver, from the media proposal
- The channel's or sales house's official Spot Length Coefficient grid for that daypart, from the rate card or annual sales conditions annex
- The current 30" CPP benchmark for the same target audience, from the rate card or the last closed deal at that level
- Target audience definition the wTRP is weighted against (e.g. Adults 25-54), from the campaign brief
The procedure
- Pull the 15" spot's quoted price and its wTRP delivery from the seller's proposal
- Look up the Spot Length Coefficient for 15" against 30" in the channel's rate card for that daypart
- Divide price by wTRP to get the 15" CPP
- Divide the 15" CPP by the coefficient to get the 30"-equivalent CPP
- Compare the 30"-equivalent CPP against the standing 30" CPP benchmark to flag over- or under-pricing
- Multiply the normalized CPP back by the wTRP as a cross-check that it reconciles to price divided by coefficient
Worked through with numbers
Seller quotes a 15" spot at €4,200 for a schedule delivering 25 wTRP on Adults 25-54. The channel's rate card lists a 15" coefficient of 0.62 for that daypart. CPP at 15" length: 4,200 / 25 = €168 per point. Normalized to 30": 168 / 0.62 = €270.97 per point. The standing 30" CPP benchmark for this audience is €260. The 15" quote, once normalized, runs about 4% above the 30" benchmark, so it is not the discount it looks like at first glance and is worth a counter.
Where it goes wrong
- Halving the 15" price to estimate 30" cost instead of dividing by the actual coefficient, which overstates the discount since SLC(15) usually sits well above 0.5
- Pulling last year's coefficient instead of the current rate card's daypart-specific figure, since sales houses revise these grids with each negotiating cycle
- Comparing the raw 15" CPP straight to the 30" benchmark without normalizing first, which makes every short-form quote look cheaper than it is
- Mixing weighted wTRP from the proposal with an unweighted GRP benchmark, since the coefficient and benchmark only line up when both sides use the same targeting base
How to know it is right
Multiply the normalized 30" CPP by the wTRP and confirm it reconciles to price divided by coefficient, then confirm the result falls inside the range of recently closed 30" deals for that audience.
Terms used