A yield case should explain what capital is doing, who funds the return, how long the conditions must hold, what gets deducted, and how principal can be impaired. If one part is missing, the headline rate is not enough.
Define the principal, denomination, liquidity requirement, time horizon, and acceptable access constraints. Capital needed for near-term obligations should not be modeled as though it can remain undisturbed.
Amount, currency, earliest use date, withdrawal constraints, and the consequence of delayed access.
P = principal available
T = usable duration
Trace the return to an economic source: public debt interest, borrower demand, credit spread, transaction fees, or token emissions. Separate durable cash flow from incentives that depend on continued issuance or subsidy.
Who pays? Why do they pay? In what unit? What causes the rate to reset, decline, or disappear?
gross return = P × r × T
List the conditions required for principal and income to arrive as expected. Include credit, counterparty, duration, liquidity, operational, custody, and—where relevant—smart-contract risk. A risk that cannot be quantified still belongs in the decision.
Write the loss path in one sentence. If the sentence cannot be written plainly, the mechanism is not yet understood.
expected ≠ guaranteed
uncertain ≠ zero
Deduct management charges, transaction costs, spreads, taxes where applicable, idle periods, conversion costs, and inflation. Compare results in the unit that matters to the capital owner—not merely the unit in which rewards are quoted.
Use assumptions with dates and sources. Run a lower-rate, higher-cost, and early-exit case before accepting the base case.
net = gross − fees − friction
real ≈ net − inflation
Each construction should fit on one page before it enters a portfolio discussion. This is a documentation frame, not a recommendation or forecast.