24-08-2026: Perp Leaderboard ROI Corrections

Affected endpoints: perp-leaderboard

Two defects in the roi calculation were corrected together. Both change the values returned by the roi field and the behaviour of the roi range filter. They shipped in a single release so roi moves once.

ROI is computed as:

roi = total PnL / (traded notional + notional of positions still open)

One defect was in each term of that denominator.

1. Traded notional was measured in coin units, not USD

The traded-volume term summed position sizes rather than price x size, so the denominator mixed coin units with the USD open-position term. The result was neither a ratio nor a percentage, and its magnitude scaled with the inverse of the coin's price.

Two traders with an identical 10% return were reported as:

Trader	Position	True return	Previous roi
A	1 BTC, $100,000 notional, $10,000 profit	0.10	10000
B	1,000,000 DOGE, $100,000 notional, $10,000 profit	0.10	0.01

This affected every row. Before the fix, 27% of traders showed a return above 100%, and ordering by roi effectively ranked traders by profit per coin traded rather than by return.

2. Open exposure netted longs against shorts

The open-position term summed each position's signed notional and then took the absolute value, so a long and a short in two unrelated coins cancelled. A book long $3.6M gold and short $3.6M S&P 500 was recorded as $25,681 of open exposure rather than $7.2M. It now sums each position's absolute notional.

This affected traders holding more than one position — about one in eight of them, by a median factor of 2.4x. Its effect on roi is much smaller than defect 1, because the traded-notional term dominates the denominator for anyone trading actively.

What this means for roi

• roi is a fractional ratio: 0.15 means 15%, -0.20 means -20%. It is signed, so a loss is negative.

• It measures PnL per dollar traded, not return on capital. A position that was opened and closed contributes both fills to the denominator, so a round trip roughly doubles it.

• The denominator also includes the notional of positions still open, so a trader with a small amount of trading and a large open book has a much larger denominator than their traded volume alone suggests.

• The roi range filter uses the same unit. {"min": 0.1} selects traders returning 10% or better.

• Ordering by roi now ranks traders by return.

Action required: if your integration filters or thresholds on roi, convert your bounds to fractions. A filter of {"min": 10} intended as "10% or better" becomes {"min": 0.1}. If you display roi as a percentage, multiply by 100.

Relationship to tgm/historical-perp-leaderboard

Values from the timestamp-certified tgm/historical-perp-leaderboard endpoint are unchanged: it already returned a fractional ratio and already summed absolute per-position notionals. After these corrections both endpoints use the same unit and the same denominator definition.

They can still return different numbers for the same trader. This endpoint values open positions at the current mark while the timestamp-certified route is as-of throughout, so a historical date range on this endpoint mixes the current open book into a past window.