Methodology
What we measure. How we calculate it. Where the evidence ends.
On this pagePortfolio intelligence should be open to examination. This reference explains the calculation rules, the populations they measure and the assumptions behind them. Read measured facts, estimates and scenarios on their own terms.
Method reviewed
Reviewed calculation methods. Prices, fund holdings and individual analyses carry their own data dates; the date here describes this reference.
Start with the population and denominator. Then distinguish what was observed, what was reconstructed, what was assumed and what was chosen. The same number can answer very different questions under a different scope.
Positions, transactions, prices and fund disclosures describe dated observations. Their completeness, currency, income basis and age determine what can be measured.
A ledger and historical prices can reconstruct a past book. Missing valuations, inferred opening positions and carried prices remain approximations; reconstruction is not an audited account statement.
Proxies, covariance estimates, cost estimates and future paths depend on assumptions. A model can reconcile arithmetically and still omit a material source of uncertainty.
Mandate weights, score curves, coverage floors and trading thresholds encode a chosen rule. Research can inform the decision without validating that particular setting or your investment policy.
Keep the valuation and transaction snapshot, dated price and FX inputs, classifications, scope, settings and calculation version. Simulations also need the random seed and path count. Public module links below pin a specific revision; a README, implementation and test each answer a different question. Licensed market histories and connected-account orchestration are not made public by publishing a calculator.
Worked examples show identities and edge cases. Implementation tests check declared behavior. The reference-risk review also records arithmetic, matrix and selected sensitivity checks. None of these alone establishes predictive accuracy, optimal policy, investment suitability or an independent platform audit. Open each chapter's details for the important counterexamples and remaining limitations.
| Reading | What is measured |
|---|---|
| Portfolio intelligence | All imported depots owned by the customer, pooled in one reporting currency. The depot named by an analysis route does not narrow this population. Accounts and assets you have not supplied remain outside the measurement. |
| Equity X-Ray | The underlying equity population. Whole-portfolio exposure and equity-only concentration use different denominators; bonds, cash and physical assets do not become companies. |
| Mandate issuer limit | The equity portion of the core portfolio across imported depots. Satellite holdings are excluded before look-through. |
| Net worth | The supported recorded wealth categories, less liabilities. This broader wealth view is not the denominator of the portfolio mandate score. |
01
Portfolio analysis follows a structured process that runs automatically and deterministically.
Calculation
value = quantity × usable price × FX conversion factor weight = value / total valued assets in the stated scope
Convert into one currency before adding values. An unknown asset classification stays unknown; a missing price is not a zero-value holding. An incomplete valuation qualifies the scope of any subtotal.
Illustrative example, not market data
If the measured portfolio contains 6,000 in equities and 4,000 in bonds, the equity allocation is 60%. This says nothing about a property or account outside that portfolio.
02
A return starts with a defined book: its assets, valuations, funding and income. TWR describes the investment path after adjusting for funding. MWR describes the experience of money invested on particular dates.
We link subperiod returns using available valuations and a declared funding-boundary convention. Missing valuations limit the result even when the arithmetic reconciles. Contributions, currency effects and benchmark differences answer separate questions.
03
Risk depends on the question, measured population and observation window. Historical statistics cannot describe every way a plan can fail.
Realized account risk, weekly holdings correlations, reference covariance, issuer concentration and future goal scenarios use different evidence and assumptions. Issuer breadth does not establish low market risk. Historical covariance does not measure future risk.
Volatility and Sharpe use consecutive cash-flow-adjusted simple valuation returns; drawdown uses the TWR unit-wealth curve. Weekly diversification uses aligned instrument histories. Window, currency, data basis and coverage qualify every reading.
04
Equity look-through measures the companies behind direct shares and eligible equity funds. It does not turn every asset class into equity exposure.
Fund constituent data comes from provider disclosures and is cached. What is shown is the provider's own as-of date, not the time of retrieval.
Calculation
company exposure = direct weight + Σ(fund weight × constituent weight) overlap(A, B) = Σ shared securities min(weight in A, weight in B)
Exposure is weighted by what you own. Pairwise fund overlap describes the two funds themselves and is independent of the amounts you hold. Incomplete constituent lists can understate both; an empty overlap list does not prove zero overlap.
Illustrative example, not market data
A fund at 60% of your portfolio with 5% in a company contributes 3% exposure. A direct 2% holding brings the total to 5%.
Calculation
issuer weight = attributed issuer value / equity-book value HHI = Σ issuer weights²; effective issuer count = 1 / HHI
Unattributed equity remains in the denominator. HHI and its inverse describe concentration, not statistically independent bets or a probability of loss. With incomplete identity coverage, observed weights are lower bounds and concentration can look too low. The separate company-risk reading includes eligible corporate bonds and has its own denominator.
Illustrative example, not market data
With full coverage, two issuers at 50% each give HHI 0.5 and an effective count of 2. Twenty fund wrappers do not necessarily mean twenty independent exposures.
05
The mandate score measures the imported portfolio against your signed rules. It does not assess whether those rules suit your needs.
Version 8 combines measured rules with limits on compensation between strong and weak results. Read individual verdicts, scopes and coverage alongside the score. It does not predict returns or loss probabilities.
Weights, curves and guardrails are Investboard policy choices. Composite-indicator research informs their disclosure; it does not validate these settings or establish that a higher score improves investment outcomes.
06
Observed returns already reflect fund expenses embedded in fund value and the costs present in recorded flows. We preserve that return and explain estimated embedded expenses separately. Recorded sale proceeds can already include tax, so the starting return is not uniformly before tax.
The German after-tax estimate uses transaction and tax-profile evidence, accounting for embedded sale tax before adding further modeled drag. These estimates are not broker settlements or tax certificates.
Calculation
known annual cost = Σ(covered fund value × annual cost rate) covered-fund TER = known annual cost / covered fund value
This is a current annualized estimate. Unknown charges remain outside the known subtotal, with coverage disclosed. It does not imply the same rates applied throughout the past.
Illustrative example, not market data
A 10,000 EUR portfolio with 6,000 EUR in a fund at 0.20% and 4,000 EUR cash has 12 EUR of known annual fund cost. The fund TER is 0.20%; the whole-portfolio known cost rate is 0.12%.
07
The net-worth view sums six categories and converts everything into euro as the single reporting currency.
Once a day one level per user is written, freshly recomputed and never from a cache. The run is skipped when the price refresh has not succeeded within the last 24 hours.
Calculation
net worth = supported gross assets − liabilities value in EUR = native value × native-to-depot FX × depot-to-EUR FX
Wealth reporting uses EUR. Portfolio analytics may use the portfolio or selected scope's reporting currency. Historical transactions and valuations need dated currency evidence; today's FX rate is not a substitute for a missing historical fixing. A listing currency is also different from a company's economic currency exposure.
Illustrative example, not market data
A hypothetical 1,000 USD holding at 0.90 EUR per USD contributes 900 EUR. Adding 1,000 USD directly to 1,000 EUR would mix units.
08
Goal projections calculate outcomes under specified growth, volatility, contribution, inflation and tax assumptions. Their probabilities are conditional model frequencies.
Independent normal shocks affect monthly log growth before contributions arrive. Annual growth anchors median compounding for an untaxed lump sum. This differs from deterministic calculator scenarios, recorded performance and cash affordability.
Percentile lines summarize each month; success counts terminal target outcomes. Fixed model parameters omit some uncertainty about future wealth.
09
Stress replay applies a named historical episode or assumed shock to today's valued holdings. It describes vulnerability under that scenario, without assigning a probability or reproducing your actual past portfolio.
Direct security history, sector proxies, asset-class assumptions and FX evidence retain different meanings. A complete current valuation is required; scenario coverage can still be partial. Read the modeled subtotal and excluded holdings before treating the percentage as a whole-wealth loss.
10
The tax calculation models the German tax waterfall for capital income in detail:
Gross capital income
Dividends, realized capital gains, advance lump sums (Vorabpauschale)
Partial exemption (Teilfreistellung)
Depending on fund type: 30% (equity funds), 15% (mixed funds), 60% (real-estate funds), 80% (foreign real-estate funds)
Loss offsetting (Verlustverrechnung)
Equity losses offset only equity gains, other losses offset all remaining capital income
Saver's allowance (Sparerpauschbetrag)
EUR 1,000 (individual) or EUR 2,000 (joint filing) is deducted
Flat capital-gains tax (Abgeltungsteuer)
The base special rate is 25%; eligible foreign-tax credits and church-tax deductibility modify the calculation under § 32d EStG
Solidarity surcharge (Solidaritätszuschlag)
5.5% on the Abgeltungsteuer
Church tax (optional)
8% or 9% of the resulting capital-income tax, where applicable. The tax base is adjusted for church-tax deductibility rather than adding this to an unchanged 25% rate
This is a German private-investor tax model for capital income under EStG §20, not a universal tax calculation for every supported website language. Fund classification, tax year, loss pools, allowances and the recorded profile determine the result. Vorabpauschale uses the relevant annual base rate, statutory cap and acquisition-year adjustment. Estimates do not replace an individual tax review or a broker certificate.
11
Investboard sources market data from specialist market-data providers:
Data quality is monitored continuously. The user is informed of discrepancies or missing data points.
12
Rebalancing restores a chosen allocation under stated constraints. It does not guarantee higher returns or protection from falling markets.
A policy specifies review timing, trading triggers, destinations and acceptable costs. Investboard applies signed corridors, available funding, sale restrictions, minimum trades and tax evidence. Generated scenarios remain conditional on those inputs.
Calculation
drift = actual weight − target weight target amount after contribution = target weight × (portfolio value + contribution)
A signed target range and distance from the target are separate readings. Rebalancing scenarios depend on budget, minimum transaction size, sale restrictions and tax evidence. A calculated scenario is not proof of a globally optimal allocation or an executable order.
Illustrative example, not market data
An equity weight of 65% against a 60% target is 5 percentage points overweight. Whether that breaches your plan depends on the signed range.
13
Financial calculations and language-model explanations have different reliability boundaries. Deterministic services produce the measured inputs; AI turns supplied evidence into an explanation that still requires scrutiny.
A fluent answer, matching number or linked source does not by itself establish that the interpretation is correct. The calculation method, source data and explanation each need their own evidence.
14
The hardest number is the one you do not have. Investboard is built to show nothing in that case rather than something plausible.
These rules are not a promise to always be right. They are the commitment to show the gap rather than fill it.
15
Investboard communicates clearly what the platform does and does not do. Honesty about its own limits is part of the product promise.
No investment advice
Investboard is an analysis tool. The platform does not provide individual investment advice within the meaning of the WpHG (the German Securities Trading Act). All information is for illustration only.
No trade execution
Investboard does not carry out securities transactions and does not route orders to banks or brokers. Bank and custody connections are used solely to read your holdings. Strategy and analysis, not execution.
No future forecasts
The platform analyses historical and current data but makes no forecasts about future price movements or returns.
No return guarantees
Simulations and projections show ranges, not promises. Investboard names the assumptions a calculation rests on and marks what is measured against what is modeled.
External references explain the underlying conventions and German legal framework. They do not certify Investboard, validate its calibration, or replace the scope and limitations documented above.
Back to contents ↑Selected original papers, authoritative methods, official law and provider contracts are linked to the decisions they inform. Descriptions identify relevant sections and the limits of each source. Older foundational work is paired with research on estimation and model uncertainty. Publication prestige does not validate our implementation, parameters or platform.
Investor education · SEC · Investor.gov
Investor education on time horizon, risk tolerance, fund overlap and restoring an allocation. It does not prescribe a universal target or trading schedule.
Used in: Portfolio analysis ↑
Provider documentation · European Central Bank · 2026-06
June 2026 framework, pp.1–4: construction, publication and informational purpose. Reference fixings are not executable transaction rates, a complete historical feed or evidence of economic currency exposure.
Used in: Portfolio analysis ↑Net worth & currencies ↑Data sources ↑
Methodological guidance · CFA Institute · GIPS · 2020/2021
2020 standards, 2021 handbook: printed pp.100–105 for TWR and Modified Dietz; pp.109–111 for MWR; pp.85–86 for short-period annualization. These conventions do not establish GIPS compliance or exact TWR from missing valuations.
Used in: Return measurement ↑When Investboard declines to answer ↑
Provider documentation · Microsoft
Microsoft’s Syntax and Remarks document the actual/365 convention and iterative nature of a familiar XIRR implementation. This is a comparison reference, not the code or convergence policy of our solver.
Used in: Return measurement ↑
Research · Andrew S. B. Frongello · Journal of Performance Measurement · 2002
Frongello (2002), especially p.13; original paper’s publisher record. Its original recursion differs from our reversed zero-benchmark convention. The detailed formula and public attribution source establish the convention actually used here.
Used in: Return measurement ↑
Research · The Spaulding Group · Performance Perspectives · 2014-01
The original publisher’s January 2014 newsletter, pp.2–4, demonstrates future-return scaling and order-dependent contributions; it also cites Frongello’s 2002/2003 “The Recursive Family Dilemma.” Reconciliation does not select a unique attribution.
Used in: Return measurement ↑
Provider documentation · MSCI · 2026-09
September 2026 edition, §§1.7 and 2.2 and Appendix III: price, gross/net income and tax conventions. A latest-edition URL can change; matching an index name or total-return label alone does not establish a comparable benchmark.
Used in: Return measurement ↑
Research · William F. Sharpe · Stanford · 1994
The author’s “Ex Post Sharpe Ratio” and “Time Dependence” sections distinguish historical estimation, expected differential returns and sampling assumptions. They do not validate our observation calendar or configured cash rate.
Used in: Risk, drawdown and correlation ↑
Research · Andrew W. Lo · Financial Analysts Journal · 2002
Lo (2002), pp.38,40–42 and equations (19)–(20): estimation uncertainty and serial-correlation effects on annualization. Explains why an observation threshold and square-root rule do not establish precision.
Used in: Risk, drawdown and correlation ↑
Research · Harry Markowitz · Journal of Finance · 1952
Markowitz (1952), pp.80–83 and89–91: variance, covariance and diversification, with estimation and practical input limits. Establishes the framework, not the correctness of our reference mappings or future covariance.
Used in: Risk, drawdown and correlation ↑
Research · Olivier Ledoit · Michael Wolf · 2003/2004
Ledoit–Wolf, 2003 working version of the 2004 paper, §§3.1–3.3: target construction and estimated intensity. Our fixed 10% shrinkage to a diagonal is a different estimator; citing this paper does not make it fitted Ledoit–Wolf shrinkage.
Used in: Risk, drawdown and correlation ↑
Research · Dirk Tasche · 2008
Tasche, §3.1, equation (3.4a), p.8: Euler volatility contributions and their additive identity. Signed contributions describe a fixed modeled portfolio; they do not equal the impact of selling a position.
Used in: Risk, drawdown and correlation ↑
Investor education · FINRA
Why correlated holdings and overlapping funds can leave a portfolio concentrated despite many positions.
Used in: Concentration & look-through ↑
Law and official tax guidance · Bundesministerium der Justiz
The fund-law origin of the 5/40 diagnostic, including legal conditions and exceptions that the diagnostic does not fully test.
Used in: Concentration & look-through ↑
Methodological guidance · CFA Institute · 2010
Individual-investor guidance, pp.11–17; rebalancing §4c, p.17. Objectives, constraints and governance support a written mandate. These pages do not prescribe our score weights or a universally optimal trading policy.
Used in: The portfolio mandate score ↑Rebalancing & optimization ↑Limits & transparency ↑
Methodological guidance · OECD · European Commission JRC · 2008
OECD/JRC (2008), pp.24,31–35,83–85,102–108 and117–123: missing data, normalization, weights, compensation and sensitivity. Supports disclosure and robustness analysis; does not validate version 8’s curves or ceilings.
Used in: The portfolio mandate score ↑
Research · ESMA · 2025-11
November 2025 report, pp.7–9 and methods pp.53–55: product and distribution costs, estimation and overlapping remuneration. Survey findings are not an account invoice or a universal fee estimate.
Used in: Costs and after-tax performance ↑
Investor education · SEC · Investor.gov
Accessible SEC explanation of fund expenses already embedded in returns. It is a companion to ESMA’s cost analysis, not a historical TER archive or evidence of the costs on a particular account.
Used in: Costs and after-tax performance ↑
Law and official tax guidance · Bundesministerium der Justiz
The German capital-income tax rate relationship, including church tax and creditable foreign tax under the statutory conditions.
Research · ECB · Household Finance and Consumption Network · 2023
Statistics Paper 45, §2.2, especially pensions in §2.2.6 and the reference-period discussion. Supports careful wealth definitions and valuation boundaries, not equivalence to our supported categories or the survey.
Used in: Net worth & currencies ↑
Methodological guidance · NIST · Engineering Statistics Handbook
NIST gives the mean, median and distribution functions implied by normal log growth. This mathematical identity does not establish market realism, parameter calibration or forecast confidence.
Used in: Projections ↑
Research · Rama Cont · Quantitative Finance · 2001
Cont (2001), §2 and §§5–6: heavy tails, volatility clustering and dependence across time scales. Explains omissions of independent normal log shocks; it does not supply or validate our volatility tiers.
Used in: Projections ↑
Research · Ľuboš Pástor · Robert F. Stambaugh · Journal of Finance · 2012
Pástor–Stambaugh (2012), §I equations (3)–(4) and §VI: predictive variance and parameter uncertainty. Conditional simulated paths with fixed parameters omit uncertainty that can grow with the horizon.
Used in: Projections ↑
Provider documentation · European Central Bank
A medium-term euro-area policy objective. It contextualizes the fixed inflation assumption without forecasting future prices, national inflation or household purchasing power.
Used in: Projections ↑
Methodological guidance · Basel Committee · BIS · 2026
January 2026 version, §§30.27–31, 30.40–50 and 30.55–64: objectives, scenarios, data, model limits and review. Banking principles inform disclosure, without equating retail replay to supervisory testing.
Used in: Stress tests and historical scenarios ↑Limits & transparency ↑
Law and official tax guidance · Bundesministerium der Justiz
German income categories, loss offsetting and the private-investor allowance.
Used in: Tax calculation ↑
Law and official tax guidance · Bundesministerium der Justiz
The advance lump-sum assessment, annual limit and acquisition-year adjustment.
Used in: Tax calculation ↑
Law and official tax guidance · Bundesministerium der Justiz
Section 19(1) reduces disposal gains by previously assessed advance lump sums in full before the partial exemption. The statutory ordering prevents treating them as a second independent tax credit.
Used in: Tax calculation ↑
Law and official tax guidance · Bundesministerium der Justiz
Fund and investor classification determine the applicable German partial exemption.
Used in: Tax calculation ↑
Law and official tax guidance · Bundesministerium der Finanzen · 2026-01-13
Official letter dated13January 2026: 3.20% for 2026 and deemed receipt on 4 January 2027. A dated annual rate is neither a forecast of future rates nor a complete personal tax calculation.
Used in: Tax calculation ↑
Provider documentation · Twelve Data
Provider definitions for prices, time series and instrument metadata. Availability and delay depend on the dataset and instrument.
Used in: Data sources ↑
Provider documentation · Financial Modeling Prep
Provider definitions for fundamentals and fund holdings. A retrieval timestamp does not make the holdings observation current.
Used in: Data sources ↑
Research · André F. Perold · William F. Sharpe · 1988/1995
Perold–Sharpe (1988), 1995 reprint pp.151–154,158–160; footnote 8 excludes transaction costs. Explains path-dependent differences between constant-mix and buy-and-hold, without establishing a universal winner.
Used in: Rebalancing & optimization ↑
Research · Vanguard · Jaconetti, Kinniry, Zilbering · 2010
Jaconetti, Kinniry and Zilbering (2010), pp.10–11: cash-flow use and cost-dependent destinations. Historical findings are conditional on the study portfolio and assumptions. Original authored paper hosted by Indexa Capital.
Used in: Rebalancing & optimization ↑
Methodological guidance · NIST · AI 600-1 · 2024
§2.2 on confabulation and MEASURE 2.5 actions 001, 003, 006 on grounded evidence and evaluation. The guidance explains failure modes and assessment needs; it does not certify our controls.
Methodological guidance · ESMA · 2024-05-30
ESMA statement of 30 May 2024, paragraphs 5, 8–16 and21–24: output reliability, data, oversight and client interests. Its investment-firm scope does not establish Investboard’s regulatory status or compliance.
Used in: Use of AI ↑
Provider documentation · Amazon Web Services
AWS's processing and model-provider access boundaries for Bedrock. These terms do not cover a separately connected external AI provider.
Used in: Use of AI ↑
The separate reference for calculator conventions and caller-supplied portfolio snapshots. Their populations and assumptions can differ from connected-account analysis.
This review clarifies equity and core-portfolio denominators, reconstructed versus recorded history, mandate-score version 8, cost double-counting, stress evidence and the boundary between deterministic calculations and AI explanations. Calculation versions and data dates belong to each result; this page's review date never replaces them. When inputs, classifications or methods change, a recalculated figure can change without a market move.
The standard
Strategy, not trading. Clarity, not noise.
Transparent calculations, traceable methods. See it in the product.