DeFi revenue farming: calculating realized APY with real costs

DeFi dashboards often display APY generated by trading fees, lending rewards or token emissions. Those figures describe potential incentives, but they do not show what an investor ultimately receives after impermanent loss, Ethereum gas, slippage and exit costs.

A realized figure gives Australian investors a more useful measure: the annualised return based on actual proceeds, valued in Australian dollars. Calculating it requires a defined holding period, reliable transaction records and a comparison with simply holding the underlying assets.

From advertised yield to cash received

Advertised APY normally assumes rewards remain invested and compounds at a constant rate. A realised calculation instead follows the cash and tokens the position produced. The starting capital must be stated in Australian dollars, including any Australian dollar stablecoin devaluation, spread paid by an exchange, or conversion cost incurred when moving from a bank account to a wallet.

For a single deposit held for (d) days, the calculation starts with:

Net profit = exit value + reward value − initial capital − gas − trading costs

The holding-period return is net profit divided by initial capital. Annualised APY is then:

Realised APY = (1 + holding-period return)^(365 ÷ days) − 1

This annualisation is meaningful only when the time period and cash flows are genuine. A profitable two-week position can produce a spectacular annualised figure, so the underlying period should always appear beside it. A loss should normally be reported as a loss rather than annualised into a misleading number.

Building a complete profit calculation

Let the initial AUD capital be (C), the value of withdrawn liquidity be (V), and the AUD value of claimed or reliably quoted rewards be (R). Gas paid in ETH and converted at the prevailing AUD price is (G), while (S) covers DEX fees, slippage and other trading costs.

Each item should be counted once. For example, LP trading fees already reflected in the value of the withdrawn position should not also be listed as a separate expense. Unclaimed incentives are excluded unless there is a reasonable basis for valuing them at exit.

Investors who add liquidity, harvest rewards and re-enter the pool face several cash flows rather than one deposit. An internal rate of return based on dated AUD inflows and outflows is then more accurate than a single APY formula. Exchange statements, blockchain explorers and wallet exports provide the timestamps needed for this reconciliation.

Measuring impermanent loss correctly

For a standard two-asset pool, impermanent loss compares the position with holding equal quantities of both assets. Define (r) as the ending price of asset one divided by its starting price, with both prices expressed against the same asset. The conventional estimate is:

Impermanent loss = 2√r ÷ (1 + r) − 1

A result of minus 2%, for example, means the LP’s underlying inventory performed 2% below the matched holding benchmark. It does not mean two percent has simply disappeared from the investor’s entire account.

Impermanent loss becomes a realised opportunity cost when the liquidity is withdrawn and the result is compared with the benchmark. Using the actual exit proceeds in the profit calculation already captures that effect, so subtracting the dollar loss again would double-count it. A benchmark-based calculation may instead start with holding proceeds and add the difference between the matched holding value and the LP value.

This comparison should include the effect of changing pool weights, rewards and fees. The simple formula provides an estimate for a constant-product, equal-value pool, while the actual token quantities and AUD proceeds remain the final authority.

Gas, taxes and Australian market realities

Gas includes approvals, adding liquidity, swapping reward tokens, bridging assets and withdrawing. ETH-denominated gas can rise sharply in AUD if the Australian dollar weakens against the US dollar. A trader in Sydney or Melbourne funding a wallet through an AUD on-ramp also faces exchange spreads or withdrawal fees before the DeFi position even begins.

The Australian Taxation Office generally treats digital tokens as property for tax purposes. Disposals, including certain liquidity operations, can create capital gains or losses, while rewards may be assessable when received. Exact treatment depends on the arrangement and personal circumstances, so a pre-tax realised APY should not be presented as a post-tax return. Keeping acquisition costs, valuations, fees and disposal dates is essential for Australian records.

AUSTRAC registration and Travel Rule requirements affect the exchanges Australian investors use, while ASIC guidance and evolving DeFi regulation make counterparty checks increasingly relevant. These obligations are not deducted from APY unless they create a direct fee. The return calculation should, however, record whether assets pass through a registered Australian exchange, an offshore platform or a self-custodied wallet.

A ninety-day worked example

Suppose A$10,000 enters an ETH/USDC pool: A$5,000 in ETH at A$2,000 and A$5,000 in USDC at A$1.60. After 90 days, ETH trades at A$3,000 while USDC remains at A$1.60. Holding both assets would produce A$12,500.

The ETH price ratio is 1.5, so impermanent loss equals approximately minus 2.02%. The LP’s underlying exit value is therefore about A$12,247.45, a benchmark gap of A$252.55. Rewards add A$420, bringing gross proceeds to A$12,667.45.

Gas totals A$89: A$25 to enter, A$36 for reward swaps and A$28 to exit. Another A$16 is lost to slippage. Net profit is A$2,562.45, producing a 25.62% holding-period return. Over 90 days, that annualises to roughly 152%:

(1.2562445)^(365 ÷ 90) − 1 ≈ 152%

This is a pre-tax realised APY based on actual proceeds. Subtracting the A$252.55 benchmark gap again would understate the return because the reduced LP exit value is already included.

The figure that should guide decisions

A credible yield calculation should be reproducible from wallet and exchange records, identify its holding period, disclose every material cost and state whether taxes are excluded. Impermanent loss belongs in the exit-value comparison, while gas and slippage reduce the money actually received.

The yield worth remembering is therefore the auditable return in Australian dollars after the position has been valued, closed and stripped of every disclosed cost.