Identifier: C3T2L2 · Revision: 2026-10-26 · Classification: domestic

Decision and objectives

Maintain a multi-day variation and contribution ledger. The decision record must connect the exposure, cash dates and implementable contract, rather than stop at a favorable price forecast.

By the end, you can maintain a multi-day variation and contribution ledger; distinguish ending equity from external cash contributions; identify the highest cumulative funding need.

Prerequisite: C3T2L1; completed Classes 1 and 2 and the Stock Market School foundation or Forex School foundation. All cases below are hypothetical; their prices, costs, rates, dates, contractual assumptions and collateral amounts are teaching inputs, not current offers.

Mechanics

Use one row per cash event. Beginning balance plus variation settlement plus external transfers minus fees equals ending collateral equity. Required margin is a separate constraint; a top-up moves your money into the account and is not trading profit. When collateral is cash, the ledger is simple; noncash valuation and currency conversion require additional rows.

The following hypothetical policy tops up to the stated requirement at each end of day. It is a teaching convention, not a claim about current Takasbank or broker call rules.

Price and return drivers

Variation = signed contracts × multiplier × settlement change. Required top-up = max(requirement − equity before transfer, 0). With no withdrawals, final equity − total external contributions equals cumulative profit less booked charges. This identity detects double-counted contributions and missing settlement postings.

Worked case

Two long futures, TRY 10 multiplier, enter at 10,000 with TRY 30,000 cash. Day 1 settles 9,600: variation −TRY 8,000, equity TRY 22,000, requirement TRY 30,000, top-up TRY 8,000, ending TRY 30,000. Day 2 settles 9,300: −TRY 6,000, equity TRY 24,000; requirement rises to TRY 36,000, so contribute TRY 12,000. Day 3 settles 9,700: +TRY 8,000, ending TRY 44,000 against TRY 36,000 requirement, leaving TRY 8,000 excess. Total contributions TRY 50,000 minus ending TRY 44,000 reconcile to TRY 6,000 gross loss. Commission TRY 80 and external funding TRY 400 make economic loss TRY 6,480 before tax; for clarity those two costs are paid outside this collateral ledger.

Adverse case

If only TRY 15,000 reserve exists outside the initial deposit, day 1 consumes TRY 8,000 and leaves TRY 7,000. Day 2 needs TRY 12,000: shortage TRY 5,000. The profitable day-three rebound cannot finance a previous deadline. Under the hypothetical policy the intermediary may close exposure on day two, so the original final-profit projection becomes irrelevant.

Practical use

Record settlement marks, actual posting times and top-up confirmations. Check whether profits are immediately available, retained as collateral or withdrawable later. Bank transfer cutoffs, holidays, intraday calls and member add-ons can require more cash than this daily model. Include full fees and reserve financing in the economic result even when paid outside the margin account.

Reconcile the confirmation, position register and cash statement separately. Costs include the quoted bid/ask spread, brokerage and clearing charges, collateral or principal financing, currency conversion, custody where relevant, and exit or termination charges. A mark is not a fill. Any amount explicitly excluded below remains outside the reported result. Tax is excluded from these teaching cases: an actual comparison requires income year, investor residence and individual/corporate status, contract and acquisition dates, settlement form and effective law. The GIB guide, checked 2026-10-26, covers 2025 individual investment income, so its publication date alone does not settle a 2026 derivative liability.

Decision boundaries

The minimum ending balance is not the funding requirement: external contributions may already have hidden the strain. Stress the path as well as the final price. A hedge backed by an appreciating illiquid asset can still fail if it cannot produce cash before the call.

Practice and references

Exercise: begin with TRY 20,000; day-one loss TRY 3,000 and requirement TRY 22,000; day-two gain TRY 1,000 and unchanged requirement. Solution: contribute TRY 5,000 on day one; ending day two TRY 23,000; excess TRY 1,000. Contributions TRY 25,000 minus final equity TRY 23,000 equal TRY 2,000 cumulative loss, excluding fees.

Takeaway: Identify the highest cumulative funding need using the actual cash schedule, with every excluded cost and remaining exposure stated.

Reference card: viop-future. Formula: Illustrative margin top-up. Glossary: Cash funding path, External contribution. Next lesson: C3T2L3. Topic test.

Sources and verification date (2026-10-26):

Shared reference guide