Using Profit and Loss Data to Monitor Trading Systems
Summary
The document explains why traders need detailed profit and loss records: to assess results, attribute performance by instrument or strategy, compare live trading with simulations, monitor costs and realized risk, support client reporting and taxes, and scale risk to available capital. It frames accounting as part of system evaluation and ongoing risk management rather than merely a way to calculate whether an account is profitable.
It outlines possible data sources, including broker account values, position-level realized and unrealized P&L, cash and accruals, trade records, and a trader’s own histories of executions, prices, slippage, and instrument-level P&L. These records can be used to check whether costs and risk match expectations and to inform volatility-based risk scaling. The excerpt is an overview rather than a detailed accounting procedure; it does not specify reconciliation methods, valuation conventions, or how to handle discrepancies among data sources.
Key ideas
- P&L data supports performance evaluation and attribution by instrument or trading rule.
- Comparing live P&L with simulations can reveal differences in costs and realized risk.
- Broker account values, position data, trade records, and independent price histories provide complementary inputs.
- Detailed records can support risk scaling based on overall capital or volatility.
- The excerpt identifies data sources and uses but does not give a full reconciliation method.
Tags
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.