Products > Perpetual Yield Tranches > Overview

How do Perpetual Yield Tranches work?

The product offers two classes of tranches, differentiated by the level of risk and the share of underlying yield assigned to each class.
Senior Tranches
Junior Tranches
This class of tranche offers intrinsic protection on funds, given by Junior class TVL. Each pool is composed of yield-bearing tokens, and the pool’s NAV is meant to only increase. A decrease in the NAV triggers the emergency shutdown to protect Senior liquidity providers. Senior Tranches intrinsically have a first lien on the underlying assets — they’re first in line to be repaid in case of default (hack or loss of funds). This product provides full-spectrum coverage, as the loss is covered regardless of the dependency or underlying protocol that caused it. Junior TVL will cover Senior TVL from a full spectrum of oracle/smart contract risks on:
  • Idle tranches;
  • Primary yield source;
  • Secondary and subsequent yield sources are used by the primary ones.
This class of tranche achieves a greater and leveraged yield by dragging more risk, as Junior holders have a second lien or no lien at all in case of fund losses.
Junior tranche is designed to receive a higher share of yield compared to the Senior class, which will proportionally compensate their Junior counterparts for taking higher risks.

Adaptive Yield Split

The Adaptive Yield Split is a feature of PYTs that makes the APY split between Senior and Junior Tranches dynamic conditional to the liquidity deposited on each tranche side.
The implementation of AYS on PYTs lets:
  • Senior Tranche receives most of the underlying yield when liquidity is low on the Junior side (i.e. low coverage on Senior funds), or receives a guaranteed minimum portion of the underlying yield when Junior liquidity is high (i.e. high coverage on Senior funds);
  • Junior Tranche receives outperforming APYs on the Junior Tranches, no matter what the amount of deposited liquidity on the Senior is.


Assuming an average underlying APY of 10%
SCENARIO A: 90/10 TVL balance
Expected APY
Senior PYT
Junior PYT
SCENARIO B: 50/50 TVL balance
Expected APY
Senior PYT
Junior PYT

Protocols and assets

Currently, Perpetual Yield Tranches are available both on Ethereum and Polygon for different protocols and underlying assets:




Senior Tranches holders of Idle Best Yield strategy PYTs can stake the respective tranchesTokens to receive $IDLE governance tokens farmed by each Idle-based pool.
LPs receive IdleCDO_AA_StrategyName (e.g. IdleCDO_AA_idleDAIYield) for Senior deposits and IdleCDO_BB_StrategyName for asset provision in the Junior class. Both tokens are fully fungible ERC-20.
Some Tranches are labelled as Experimental, meaning there are some deposit limits (caps).

Yield and loss scenarios

These two classes of tranches have been designed and developed to meet different users' needs. Whether you’re an experienced risk-lover degen or a new joiner to DeFi amazed by its yields, this new product will offer something for you.
Given the nature of the two classes of tranches, which differ in terms of risks and gains opportunities, it is possible to explain their behavior through two scenarios: a Yield case and a Loss case
First of all, it is important to highlight that the interest earned in the pool will be split between the two classes according to a predefined ratio, which gives 10% of interest to Senior Tranches and 90% of interest to Junior Tranches.
Assume there is a pool with 1000 DAI in total with a 10% APY; these would be the scenarios:
  • In the Yield case, the interests generated in the pool (100 DAI in total) will be split as 90 DAI (90% of the interest) to Junior Tranche and 10 DAI (10% of the interest) to Senior Tranche. The current APY and the percentage of interest are higher in Junior Tranche because, as mentioned above, this class takes more risk than the Senior one and is rewarded accordingly.
  • In the Loss case, the only class of tranches affected by a possible loss will be the Junior one. Suppose, there is a 100 DAI hack loss, the Senior tranche will have the entire capital protected, while Junior tranches will bear a partial loss of the funds deposited.

Benefits of using Perpetual Yield Tranches

There are some benefits that can be achieved using this product:
  • Cheaper transactions’ deposits and redeems;
  • Governance tokens (COMP, stkAAVE, LDO, CVX, CRV) automatically harvested to boost yields;
  • Deposits and withdrawals are possible at any time due to no locking periods or epochs;
  • Only a 10-15% performance fee of the interest generated is applied.