Balance growth is a liability
if it destroys margin.
A deposit is not an asset; it is a funding source. If the rate required to acquire or retain a cohort exceeds its transfer value, you are buying liquidity at a loss.
The Portfolio Event
Rate sensitivity defines the cohort.
Not all balances are created equal. A cohort acquired through a high-yield promotional rate behaves fundamentally differently than a core transactional checking cohort.
When market rates shift, the composition of your deposit base dictates your economics. Highly rate-sensitive cohorts (high beta) require aggressive repricing to prevent mass attrition and withdrawal outflows. Sticky cohorts (low beta) provide stable, expanding margins during rate hikes. Understanding the exact mix of these behaviors is how modern treasuries manage liquidity risk.
The Decision
Paying for balances you don't need.
When liquidity is tight, the reflex is to raise deposit rates. But a uniform rate hike often overpays sticky cohorts who weren't going to leave anyway, destroying overall margin to capture marginal new volume.
Portfolio Economics
The definitive funding value.
Cohort Brain explicitly models deposits as funding instruments. We calculate the exact economic contribution of every deposit cohort by netting its costs against its market funding value.
For any cohort, the Funds Transfer Pricing (FTP) rate dictates its value to the bank. Subtract the posted interest rate paid to the customer and the localized servicing costs. What remains is the pure net margin. If that margin turns negative, the balance is a liability.
Built on the Cohort Brain platform.
Your deposit models run on the exact same governed engine as your lending portfolios. Evaluate macroeconomic sensitivities, enforce guardrails like liquidity coverage, and present unified ALM forecasts.
Explore the operating system →See your next portfolio decision
before you make it.
A focused working session on your portfolio — cards, BNPL, term loans, mortgages or deposits. No pitch deck. No sequence.