Currency Exposure Netting: Seeing What You Really Own

[Fairman]

Currency Exposure Netting: Seeing What You Really Own

Open trades on several pairs, and you may hold more of one currency than you realize. Netting the exposure reveals the true picture.

Each pair involves two currencies. Buying EUR/USD means long euro and short dollar. Selling GBP/USD means short pound and long dollar. Add buying AUD/USD, and you have long euro, long Aussie, short pound, and a combined short-dollar position from two trades and long dollar from one.

To net it, list each trade by currency and direction, with its size or risk. Short dollar in two trades, long dollar in one, produces a net short dollar position of one trade's size. The offsetting trades cancel part of the exposure, and you pay spreads on both.

This often shows hidden concentration. Five trades that look like five independent ideas may all be a bet on dollar weakness. Or it may show unintentional hedges, where two positions cancel each other and produce nothing but costs.

A simple table works: rows for currencies, with columns for long and short risk. The net row tells you which currency you are really betting on.

Large net exposure to one currency means a single news event can hit all your trades.

Practical step: create a currency exposure table for your current or typical trades, and note the largest net position.

[Fairman]

Worked example of netting. Long EURUSD, short USDJPY, long GBPUSD. That's short dollar three times. If the dollar strengthens on one data release, all three trades lose together. Laid out by currency, it's obvious. Laid out by pair, it's easy to miss. A simple table with one row per currency and a running total in lots helps. After each new trade, update it. If one currency shows up three times in the same direction, either reduce the newest position or accept that you're making one bigger bet and size it as such. It takes a minute and catches the most common hidden risk in multi pair trading, especially on busy US data days.

[Fairman]

A quick way to do it: write each currency on a line and add +1 or -1 for each trade. EUR +1, USD -3, GBP +1, JPY +1. The biggest number tells you where your real exposure is. For more accuracy, use the risk amount instead of plus or minus one, since a 1 percent trade and a 0.5 percent trade shouldn't count the same. Then set a limit per currency, say 2 percent net at most in any one currency. When a new setup would push the dollar line past that, it either waits or replaces an existing trade.

[FXS Prop Desk]

Netting is a valuable exercise, especially for traders who hold several dollar pairs at once. A simple tool: a spreadsheet with one row per trade and one column per currency, entering + for long and - for short in risk units. The column totals show the real exposure.

In the example, the USD column would show the net short. It quickly reveals when three "different" trades are effectively one large position on a single currency. Some traders also set a maximum per currency column, e.g. 2R, to stop this before it happens.

[Shadow Trader]

The case where netting has helped me most is the accidental synthetic. Long EURUSD plus short EURGBP leaves the euro at zero, and what remains is long pound and short dollar, which is just a GBPUSD long paid for with two spreads.

I had that exact pair on one morning without noticing. Each trade had its own reason, but the table showed I was running one GBPUSD idea through two tickets at double the cost.

One reservation about the plus and minus counting in Fairman's third post. Every pair has two legs, but on a given day one leg usually drives it, and on a UK CPI morning a GBPUSD long is mostly a pound trade rather than a dollar one.

So I weight the legs on event days. If the release is a pound number, the GBP column gets the full risk and the USD column gets half, which is rough but closer to how the position actually moves.

On FXS Prop Desk's 2R per currency cap, does anyone count gold in the USD column? My XAUUSD longs behave like short dollar trades on most US data, so I put them there at full risk.