sUSDS, issued by the Sky Protocol smart contracts under the governance of SKY tokenholders, is a yield-bearing savings token representing USDS deposited into the Sky Savings Rate contract and accruing protocol revenue through an increasing exchange rate [S1][S2].

Each sUSDS represents USDS supplied to the Sky Savings Rate (SSR) contract, where the sUSDS-to-USDS exchange rate grows automatically over time, auto-compounding without lockups [S1][S3]. Yield is funded by real protocol revenue delivered through the Sky Agent Network rather than by token emissions [S1]. The SSR is variable, set through SKY governance, and can drop significantly, go to zero, or become negative [S2][S1]. Conversions between USDS and sUSDS carry zero entry and exit fees; holders bear network gas fees and their own taxes [S1][S4].

There is no corporate token issuer; sUSDS is issued by permissionless, non-custodial smart contracts governed by SKY tokenholders [S3][S2]. The only named legal entity is interface operator Skybase International, governed under Cayman Islands law, which disclaims being a broker, dealer, exchange, investment adviser, custodian, or financial service provider of any kind [S4]. sUSDS represents a yield-bearing deposit claim, not a regulated instrument or fund interest [S2]. Users must reach the age of majority, must not reside in prohibited jurisdictions, appear on OFAC lists, or use VPNs, and some features are unavailable to U.S. residents [S4][S2]. sUSDS redeems to USDS anytime without fees, holders retaining control over their cryptoassets [S1][S4].

sUSDS is an ERC-4626 yield vault token that remains ERC-20 compatible while accruing yield [S1]. It is issued on Ethereum and other supported networks, with cross-chain transfers enabled via SkyLink [S1][S5]. sUSDS is minted by supplying USDS and redeemed by returning sUSDS, settling onchain at the prevailing exchange rate; real-time rate analytics are published at info.sky.money [S1][S2].

<Sources
  retrievedAt="2026-06-19"
  items={[
    { id: "S1", url: "https://sky.money/susds" },
    { id: "S2", url: "https://docs.sky.money/legal/skybase-international/user-risks.md" },
    { id: "S3", url: "https://sky.money/" },
    { id: "S4", url: "https://docs.sky.money/legal/skybase-international/terms-of-use.md" },
    { id: "S5", url: "https://docs.sky.money/legal/skybase-international/user-risks" },
  ]}
/>


# Asset senders (daily) methodology

## 1. Overview

Asset senders (daily) is calculated as the number of unique addresses that initiate asset transfers within a fixed 24-hour window. Daily activity is measured from 00:00 UTC to 23:59 UTC for each tracked asset. Active transactors are isolated from passive recipients by identifying only the sending addresses of transactions. This metric is utilized to evaluate the daily active user base and transaction utility of tokenized assets across multiple blockchain networks.

## 2. Data sources

- **EVM chain events**: ERC-20 `Transfer` events, covering EVM-compatible chains (Ethereum, Arbitrum, Base, Polygon, Optimism, and others)
- **Solana instructions**: Token transfer instructions, covering Solana
- **Aptos, Cardano, Stellar Classic, and Sui events**: Token withdraw events, covering Aptos, Cardano, Stellar, and Sui
- **Near, Algorand, Injective, Ripple, and Stellar Soroban events**: Token transfer events, covering Near, Algorand, Injective, Ripple, and Stellar
- **Polkadot Asset Hub events**: `Transferred` events from the `assets` pallet, covering Polkadot Asset Hub
- **Asset metadata**: Token addresses and chain configurations

## 3. Step-by-step calculation

### Component A: Extract sender addresses

- **Purpose**: Identify and extract the unique sending addresses for each asset transfer across all supported chains.
- **Logic**: On EVM-compatible chains, sending addresses are extracted from the `from` field of ERC-20 `Transfer` events, excluding the zero address to filter out mint transactions. On Solana, sending addresses are extracted from the authority address field of token transfer instructions. On Aptos, Cardano, Stellar Classic, and Sui, sending addresses are identified from the account address field of token withdraw events. On Near, Algorand, Injective, and Stellar Soroban, sending addresses are extracted from the sender address field of token transfer events, with null addresses excluded. On Ripple, sending addresses are extracted from token transfer events where the transfer value is negative. On Polkadot Asset Hub, sending addresses are extracted from the event data of `Transferred` events emitted by the `assets` pallet.
- **Key fields**: `timestamp` (block timestamp truncated to daily grain), `token_address` (the contract or asset identifier), `sender_address` (the address initiating the transfer)

### Component B: Consolidate and deduplicate sender data

- **Purpose**: Aggregate sender addresses across all chains and prepare the dataset for daily unique counting.
- **Logic**: Sender records from all individual chains are consolidated into a unified dataset. For each asset on each chain, the sending addresses are grouped by day. To prevent double-counting, duplicate sender addresses for the same asset on the same chain within the same 24-hour window are removed.
- **Key fields**: `timestamp` (daily timestamp), `chain_id` (blockchain identifier), `token_address` (asset address), `sender_address` (unique sending address)

### Component C: Final aggregation

- **Purpose**: Calculate the final daily active sender count per asset and per chain.
- **Logic**: The consolidated dataset is aggregated to compute the daily active senders. Unique sending addresses are counted for each asset on a daily basis, both at the individual chain level and aggregated across all chains for multi-chain assets. If no transfer activity is recorded for a tracked asset on a given day, the daily sender count is filled with zero values.
- **Key fields**: `timestamp` (daily timestamp), `chain_id` (blockchain identifier), `token_address` (asset address), `asset_dau` (daily active senders count)

*This methodology was automatically generated by Token Terminal's methodology analyzer.*

Unique asset senders over a fixed 24-hour window.

Asset senders (daily)

Tokenized funds

Overcollateralized borrowers deposit funds into Sky and receive DAI stablecoin.

Sky is a non-custodial stablecoin protocol built on Ethereum. Sky (previously MakerDAO) was founded by Rune Christensen and launched in 2015.

SKY tokenholders own and govern the protocol. They currently take all of the total interest and PSM fees paid by borrowers (revenue). Sky’s investors include a16z, Polychain, IOSG Ventures, etc.

governance

github

twitter

discord

etherscan

website

Stablecoin issuers

Sky | Fees and revenues breakdown

Savings USDS (sUSDS) is a tokenized fund share issued by Sky.

Each token is a direct claim on the issuer.

The fund is open-ended, invests in crypto assets, locks up subscriptions for 0 months, and charges a 0% annual management fee.

Retail investors can subscribe and redeem in USDS, with a USDS 0 minimum, and holders have a right to redeem at net asset value.

sUSDS has been issued on Ethereum as an ERC-20 and ERC-4626 token since September 2024, with bridged versions on four more.

Savings USDSsUSDS