Gross, net, currency and fee basis
Match the economic definition of a return before subtracting two percentages or describing one account as outperforming another.
Added 15 October 2026
Net needs an attached definition
The word net is incomplete unless the reader knows what has been deducted. Trading commissions, spread, financing, management fees, performance fees and subscription costs are different economic items. A net account return may not include the cost a particular subscriber pays to access research. Preserve the source's actual definition instead of adding costs by assumption or treating every net label as identical. If a comparison requires a specific fee item, ask whether and how it appears in each record.
Do not mix transaction and account measures
A trade can have an entry-to-exit percentage while an account return depends on position size, concurrent exposures and available capital. Adding subscription fees to a trade percentage without a capital denominator does not produce an investor return. A research model summary can be valuable while measuring something different from a funded account. Keep the object being measured in the column heading. A clear label is more useful than a precise number whose denominator changes between rows.
Currency is part of identity
The same holdings can have different measured returns when expressed in different base currencies. A conversion needs appropriate rates and valuation times, not just a currency symbol changed in a spreadsheet. A current exchange rate is not automatically the correct rate for a historical flow or period return. Our comparability checker treats a different supplied currency as a mismatch. It does not fetch rates or convert records, so a matching result never implies that it has independently reconciled currency exposure.
A controlled mismatch example
In the fictional comparison packet, two records share the issuer, event, division, dates, status and declared calculation basis. Changing the currency label in one row makes them incompatible under the tool's rule. Changing net-time-weighted to gross makes a second mismatch. The tool names those fields and withholds a percentage-point difference for that pair. Editing labels back to match changes the input declaration only. It does not establish that the actual accounting behind either record has been inspected or that the declaration is correct.
A difference is not a performance attribution
Where the labels match, subtracting one supplied return from another gives a descriptive difference in percentage points. It does not explain why the difference arose. Costs, exposures, trade timing, account constraints and execution can all require separate evidence. Do not describe the subtraction as alpha, skill or a fee impact without the appropriate method and source records. Comparing two compatible values is only the beginning of an attribution exercise, not proof that an isolated strategy decision caused the difference.
Preserve unknown fields explicitly
A missing basis or currency is not equivalent to an ordinary text label such as net or USD. The tool accepts null for an unknown comparison key, flags it as missing and declines the narrow difference calculation for that pair. It will not infer the field from another row or a familiar account name. The export includes the supplied inputs, findings and unperformed validation fields. For a real decision, return to authentic statements and the applicable reporting policy rather than replace missing definitions with a convenient default.
An authored reading exercise
Take two fictional twenty-percent return labels. One is gross in XCU; the other is net in YCU. Equal numerals do not make the records equal. The checker should name the basis and currency mismatch and withhold its narrow difference calculation. It should not output zero and let the reader infer equivalent outcomes. A later authentic accounting reconciliation could support a new comparison, but simply editing the labels does not perform one. This controlled example supplies no fee assumption, historical exchange rate or actual account result.