How Sensitivity Is Calculated
The ranking is arithmetic and reproducible from Monthly History alone. Read this before arguing with it.
The problem with elasticity
Brightwell's identity is Sessions x Enquiry rate x Lead-to-order rate x Average order value. Differentiate a product with respect to any one factor and the elasticity is exactly 1. Lift any driver ten percent and revenue rises ten percent, whichever one you picked.
So the Elasticity column reads 1.00 on all four rows. That is the structure of the identity rather than a rounding artifact. It also means the usual instruction to work your highest-leverage driver is an instruction to choose between four identical numbers.
What replaces it
The drivers are identical in what a one percent move produces. They are nothing like identical in how far they have ever moved. Sessions have ranged from 33,900 to 53,600 across twenty-four months. Average order value has ranged from $1,836 to $2,014 and never left that band.
| Driver | Own P90 | Elasticity | Releases | Share of gap |
|---|---|---|---|---|
| Sessions | 51,110 | 1.00 | $85,097 | 83.1% |
| Lead-to-order rate | 24.82% | 1.00 | $45,662 | 44.6% |
| Enquiry rate | 3.37% | 1.00 | $41,193 | 40.2% |
| Average order value | $1,992 | 1.00 | $24,955 | 24.4% |
Identical elasticity. A 3.4x spread in what a best-ever month is worth. Nothing on that table closes the $102,389 gap, and that finding only exists because the levels are bounded by history instead of chosen.