A standard trade log records what you did. It says nothing about the state you were in when you did it — and since your worst trades are driven by emotion, that's the most important data you're not collecting. An emotional ledger tracks your mental state alongside your trades, and it reveals patterns no P&L column can.
What to record
Keep it dead simple or you won't do it: for each trade or session, note your emotional state (calm, anxious, bored, euphoric, frustrated, rushed) and, briefly, why you took the trade (setup, or a feeling — FOMO, revenge, boredom). A quick rating — how disciplined did I feel, 1–5? — works too. The goal is to timestamp your internal state so you can later correlate it with results.
What it reveals
Over time, the correlations jump out: your revenge trades cluster after a loss and lose money; your euphoric trades cluster after a big win and give it back (size creep); your bored midday trades are pure negative expectancy. You'll often find that a specific feeling, not a specific setup, is your biggest leak — and you can't fix what you haven't measured. The ledger makes your emotional leaks visible and therefore fixable.
Your P&L tells you which trades lost. Your emotional ledger tells you which feelings lost — and feelings, unlike prices, are something you can learn to catch in the moment.
Turning it into control
Once you know the states that produce bad trades, you can build rules around them: no trading when you notice the revenge trigger, size down when euphoric, step away when bored or fatigued (decision fatigue). The ledger is the input to that self-awareness. Review it in your weekly ritual alongside the numbers — the emotional patterns and the P&L patterns usually tell the same story from two directions.