ART-375 · Funds/NAV Family

Compute Fund Expense Ratios

Computes a fund's gross expense ratio, net expense ratio, and Total Expense Ratio (TER) from supplied gross expense components (flat amounts or accruals, using the same accrual conventions as Recompute Fund NAV) and average net assets, applying any declared fee waivers or caps strictly in a declared order, using fixed-point money math throughout (no float accumulation). Waiver ordering is the substance: the order in which a fixed-dollar cap, a percent-of-remaining reimbursement, and a rate cap apply changes the net expense ratio, so the order is a required declared input, never a house convention, and every waiver's running-balance effect is returned for audit. Third entry of the Funds/NAV family, alongside Recompute Fund NAV and the forthcoming NAV-error materiality tester.

Fixed-Point Money Math Waiver Order Is a Declared Input Not a Compliance Determination
🔒 All inputs are processed locally in your browser. No data is transmitted. Do not enter real personal data — use synthetic or anonymised inputs only.
What this does NOT prove
Every expense component, average-net-assets figure, and waiver term here is supplied by you and merely asserted: this tool performs zero fund-administrator or market-data lookups (zero-egress, no network calls of any kind). It recomputes the arithmetic over your declared inputs, applying waivers strictly in your declared order, and attests that computation ran correctly. This is never an opinion on whether a fund's reported expenses are accurate, and never a compliance determination. 40-Act/UCITS citations below are informative context only.
Fund & Period
Average Net Assets, Decimal Places & Rounding
Gross Expense Components (JSON array: flat `amount`, or accrual via `principal`/`annual_rate`/`days`/`day_count_convention`)
Waivers (JSON array: each MUST declare `order`; `method` is fixed_amount / percent_of_remaining / cap_to_rate)
–
Gross Expense Ratio
–
Net Expense Ratio
–
Total Expense Ratio
Component breakdown
Gross expense components
DescriptionDay-count conventionAmount
Waivers applied, in declared order (running balance)
OrderDescriptionMethodRemaining BeforeReductionRemaining After
What was NOT proven
Compliance Flags
Provenance
Fixed-point (BigInt) money math throughout: every value is parsed from its decimal string representation, never via floating multiplication, so there is no float-accumulation error anywhere in the arithmetic path. Waivers are applied strictly in ascending declared `order`; the running remaining-expense balance before and after each waiver is included so the order-sensitivity of the result is auditable line-by-line.
⚠ DECISION-SUPPORT DRAFT. Not an opinion on expense accuracy, not a compliance determination. Expense/waiver inputs are supplied and asserted only.
OpenChainGraph v0.4 artifact · execution_hash:
–


    

      
      
      
    

  


  
  









  

    
Ask your agent

    
  

  
Copy this paragraph into Claude, OpenClaw, or any MCP-aware agent to run this exact tool, with this sample, and verify the artifact.

  
Run the AINumbers MCP tool `compute_fund_expense_ratios`. Task: Compute a fund's gross and net expense ratios and Total Expense Ratio (TER) from SUPPLIED gross expense components (flat amounts or accruals, using the identical accrual conventions as recompute_fund_nav/FN-1) and average net assets, applying any declared fee waivers/caps strictly in a DECLARED order using fixed-point BigInt money math throughout (no float accumulation).
Call it with arguments: {"policy_parameters":{"fund_id":"FUND-EXP-01","period_start":"2026-01-01","period_end":"2026-12-31","average_net_assets":100000000,"gross_expense_components":[{"description":"management fee","principal":100000000,"annual_rate":0.0075,"days":365,"day_count_convention":"actual/365"},{"description":"admin fee","amount":150000},{"description":"12b-1 fee","amount":100000}],"waivers":[],"rounding":{"decimal_places":4,"mode":"half_up"}}}
Verify before trusting: call `verify_execution_hash` on mcp.ainumbers.co (https://mcp.ainumbers.co/mcp) with the parameter `claimed_hash` set to the returned `execution_hash`, passing the full artifact the run returned (the object containing `policy_parameters` + `output_payload` + `execution_hash`; equivalently `policy_parameters` + `output_payload` with `claimed_hash`), not the bare hash string.
Return the ledger link https://ledger.ainumbers.co/ so a human can re-verify without contacting us.
PII rule: All inputs are processed locally in your browser. No data is transmitted. Do not enter real personal data — use synthetic or anonymised inputs only.
Open the tool with the sample prefilled: https://ainumbers.co/chaingraph/art-375-compute-fund-expense-ratios.html#p=v1.H4sIAAAAAAAA_wGcAWP-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