The Common Currency Model
Convert every lever in the business into one shared unit so cross-team tradeoffs become arithmetic
- Difficulty
- Expert
- Time to result
- ~months to results
- Steps
- 5
- Confidence
- 93%
DoorDash quantifies every business lever — price, delivery speed, selection, quality, conversion, supply — into a common currency (gross order value and volume). Once a dollar of price cut, a minute of delivery time, a signed restaurant, and a mobilised Dasher all translate into the same unit, a marketing-versus-logistics tradeoff stops being a debate and becomes a comparison. The result is an inventory of options with known short- and long-term payoffs.
Origin
Jessica Lachs, DoorDash analytics. Lenny Rachitsky notes the same pattern was used at Airbnb, where every decision was translated into nights booked.
Core principles
- 01Cross-functional tradeoffs are only decidable if the sides share a unit
- 02Pick the currency the whole company already believes in (GOV, volume, nights booked)
- 03Every lever gets an exchange rate: what does a dollar or a minute buy?
- 04The output is an inventory of options with payoffs, which makes decisions fast
- 05Speed of decision-making is itself the payoff of the model
How to run it
- 1
Choose the common currency
Pick one or two terminal business metrics everyone accepts — at DoorDash gross order value and volume; at Airbnb nights booked. Every other metric will be expressed in these terms.
Pro tip The currency should be the thing the board and the ICs both care about, so no team can dismiss it as someone else's metric.
- 2
Enumerate the levers
List every lever the business can actually pull: price, delivery time, quality, selection, conversion/login flow, merchant acquisition, courier supply, marketing spend.
Pro tip Include levers owned by different functions — that is the point.
- 3
Estimate an exchange rate per lever
For each lever, quantify the conversion: if I lower price by a dollar, what volume do I get? If I cut delivery time by a minute? If I sign one Thai restaurant in Sacramento? If I put one more Dasher on the road?
Pro tip Attach a time horizon to each rate — some levers pay back next week, some next year.
Watch out These rates are models, not truths. Re-estimate them as the business changes.
- 4
Convert every team's goal into the currency
Whatever a team is goaled on — conversion, delivery times, merchant signups — maintain a translation to GOV and volume, so any proposed improvement can be priced.
- 5
Allocate the marginal dollar by comparison
When deciding where to spend a dollar or a team's week, compare the currency-denominated return across all levers: improve conversion, spend on marketing, onboard Dashers, sign restaurants, add grocery stores. Choose the best mix, not the loudest advocate.
Pro tip Keep the ranked list standing so decisions are lookups rather than fresh analyses.
Watch out Optimising for the currency alone can starve levers whose value shows up as fail-state avoidance rather than volume — pair this with fail-state goals.
In the wild
DoorDash can ask what a dollar off the price buys in volume and what a minute off delivery time buys in volume. Because both are in the same unit, the marketing team's and logistics team's proposals sit on the same table and can be ranked instead of argued.
→ Faster and better decisions across a four-sided marketplace, with a standing view of what the company gets for a dollar depending on where it is spent and over what timeframe.
Selling a Thai restaurant in Sacramento is translated into expected incremental GOV from consumers, so a sales action can be compared directly against a product improvement to the login flow.
→ Sales, product, and supply investments become comparable in one currency, letting DoorDash pick the right mix of actions across the whole business.
Common mistakes
Letting each function argue in its own units
Conversion points, minutes saved, and merchants signed are incommensurable. Without a common currency the loudest or most senior voice wins the tradeoff.
Building the model but not the inventory
The speed benefit comes from having a pre-computed, standing list of options and payoffs. Rebuilding the analysis every decision defeats the purpose.
Treating exchange rates as permanent
Elasticities shift as the business scales and mix changes. Stale exchange rates give confidently wrong allocations.
Is it for you?
Best for
Analytics and strategy leaders at multi-sided marketplaces or operationally complex businesses who must arbitrate investment between supply, demand, product, and quality teams
Not ideal for
Early-stage products with a single lever and no cross-functional tradeoffs to arbitrate, or businesses whose terminal metric is not yet known
From the transcript
“we spend a lot of time quantifying things in terms of a common currency”
“we've tried to quantify all of the levers of our business price selection quality um in common terms”
“if I were to lower price by a dollar what would I get in terms of we'll say volume”
“it definitely helps us to make decisions more quickly and hopefully better decisions”
From the episode
Building a world-class data org
Jessica Lachs (VP of Analytics and Data Science at DoorDash)