Aggregated APY (AAPY)
Overview
"Aggregated APY" (Annual Percentage Yield) represents a consolidated APY calculation across multiple Cauldron liquidity pools, referred to as "micro-pools." Each micro-pool follows the Constant Product Market Maker (CPMM) model, contributing liquidity individually. Aggregating APY provides a comprehensive view of yield across all pools in a period, while weighting pools proportionally to their liquidity to ensure that larger pools have a more substantial impact on the final APY.
Key Concepts
- Constant Product Market Maker (CPMM):
Each micro-pool is governed by the CPMM model, where the product of the reserves of two assets remains constant:
- \( x \) represents the reserve of one asset (e.g., BCH).
- \( y \) represents the reserve of the paired token.
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\( k \) represents the constant product, which increases over time as liquidity and yield accumulate.
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Annual Percentage Yield (APY):
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APY is calculated for each pool based on the yield generated over time.
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Weighted Aggregation:
- Larger pools that have existed for a longer time contribute more to the aggregated APY. To achieve this, the calculation uses the square root of each pool’s \( k \) value at the end of the period as a proxy for the pool’s size. This weighting ensures that larger pools, which have more liquidity and more stable and less gameable yield, have a proportionally larger impact on the aggregated APY.
Calculation Methodology
1. Calculate Pool-Specific APY
2. Weight Each Pool’s APY by Size and Active Duration
To accurately aggregate APY across all pools, we use the square root of the final \( k \) value to weight each pool. This approach considers the pool’s liquidity and yield accumulated up to the end of the period:
Where:
$$ \sqrt{k_{\text{final}}} $$ represents the square root of the pool’s final $ k $ value, providing a size-based weight.
3. Calculate Aggregated APY
Finally, the aggregated APY is computed by summing each pool’s weighted APY and dividing by the total weight across all pools:
This formula ensures that the aggregated APY reflects contributions from all pools, with larger, longer existing pools having a proportionally greater impact on the result.