Key Concepts Explained
Index Price serves as a critical benchmark in cryptocurrency investing, representing the average market price across major exchanges. It forms the primary component in calculating the Mark Price.
Mark Price determines fair position valuation, enabling accurate calculation of unrealized P&L and liquidation thresholds. This mechanism enhances market fairness and reduces manipulation risks.
Perpetual Futures Pricing Mechanisms
Index Price Calculation
BTSE Perpetual Futures Index Price = Average Spot Liquidity Mid-Price Across Top Exchanges
- Spot Liquidity Mid-Price Formula:
(Bid Price × Ask Size + Ask Price × Bid Size) / (Bid Size + Ask Size)
Data Sources: Bitfinex, Binance, Huobi, and Coinbase Pro
- Price stabilization: Excludes highest/lowest values before averaging
- Exchange count varies per cryptocurrency (see reference tables)
When 5 reference prices exist: Discard extremes and average remaining 3
Mark Price Determination
BTSE Perpetual Futures Mark Price = (Spot Liquidity Mid-Price × 90%) + (BTSE Depth-Weighted Mid-Price × 10%)
Components Breakdown:
- Depth-Weighted Mid-Price:
Average of depth-weighted bid/ask prices - Depth-Weighted Bid:
Mean price of top 10,000 buy orders - Depth-Weighted Ask:
Mean price of top 10,000 sell orders
Example Calculation:
- Buy-side: (6,584.5 × 10,000)/10,000 = 6,584.5
- Sell-side: (6,586 × 3,467 + 6,587 × 6,533)/10,000 = 6,586.65
- Mid-Price: (6,584.5 + 6,586.65)/2 = 6,585.58
Activation Conditions:
- Max 2% deviation from BTSE futures liquidity mid-price
- Beyond 2%: Mark Price = Index Price
Quarterly Futures Pricing Models
Index Price Formula
BTSE Quarterly Futures Index Price = Spot Liquidity Mid-Price × (1 + Fair Basis)
Fair Basis Determination:
- Matched expiration dates: Use reference exchange's premium/discount
- Unmatched dates: Interpolate/extrapolate using two nearest expirations
Example Scenarios:
- Interpolation: For 03/15 expiry between 03/05-03/20 references
- Extrapolation: For 03/25 expiry beyond 03/05-03/20 range
Validation Rules:
- Reference data must be active
- Pre/post-weighting difference < 0.5%
- Non-compliance → Basis = 0%
Mark Price Computation
BTSE Quarterly Futures Mark Price = (Index Price × 90%) + (Futures Liquidity Mid-Price × 10%)
Deviation Rules Mirror Perpetual Futures:
- 2% threshold applies
- Excess deviation → Mark Price = Index Price
Frequently Asked Questions
Why do exchanges use Mark Price instead of Last Traded Price?
Mark Prices prevent price manipulation through large orders and create fair liquidation values, especially during high volatility.
How often are index prices updated?
BTSE updates index prices in real-time, typically every few seconds, using the latest exchange data feeds.
What happens if an exchange in the index goes offline?
The system automatically excludes non-responsive exchanges from calculations, using remaining active sources to maintain price integrity.
Can the weighting percentages change?
👉 Yes, exchanges periodically review weightings to reflect changing market conditions and liquidity patterns.
How does this protect against "wicking" in volatile markets?
By relying on depth-weighted averages rather than momentary spikes, the system filters out anomalous price movements.
Where can I verify current index components?
👉 BTSE provides transparent documentation listing all reference exchanges and calculation methodologies for each instrument.
Final Considerations
Understanding these pricing mechanisms helps traders:
- Accurately assess position health
- Anticipate potential liquidations
- Recognize fair value during market anomalies
For institutional traders, these transparent calculations enable:
- Better hedging strategies
- Improved risk management
- More precise arbitrage opportunities
Remember: Always cross-reference mark prices with underlying index values when making large trades during periods of market stress.