# Sky Savings Rate, USDS and DAI Supply > Track the Sky Savings Rate and realized sUSDS yield, USDS and DAI supply by chain, the collateral behind them and Smart Burn Engine buybacks, on-chain. Markdown copy of https://voltfincrypto.com/apps/sky-savings-rate-usds-dai **Question:** What is the Sky Savings Rate today, and how much USDS is earning it? - Kind: Dashboard in Voltfin Vantage - Topic: [Stablecoins](https://voltfincrypto.com/topics/stablecoins) - Chains: Multi-chain, Ethereum, Base, Arbitrum, OP Mainnet, Unichain, Solana - Status: Planned. The data is not published yet, so this page states no figure; each figure will open its receipt when it is. The Sky Savings Rate is the yield Sky governance pays to USDS holders who deposit into sUSDS, the protocol's savings token. sUSDS keeps a fixed token balance and grows in value through a rate accumulator, chi, which rises every second at the rate ssr. This dashboard reads both, along with the supply of USDS and DAI, from the contracts on Ethereum and the chains USDS has been bridged to. Sky is the renamed Maker protocol. DAI still circulates, and a converter contract swaps DAI for USDS and back at one to one, so the two are shown side by side rather than added together. DAI keeps its own savings rate, paid through the Pot contract to sDAI holders; governance sets the two rates separately. The dashboard also shows what stands behind both coins: debt drawn against each collateral type in the Vat, stablecoins held in the peg stability module and lines extended to Sky's allocators such as Spark and Grove. When surplus passes the buffer governance has set, the Smart Burn Engine spends it on SKY; those purchases are listed with their transactions. ## Blueprint ### Savings rate The rate set, what sUSDS paid and how much USDS is earning it. - **Sky Savings Rate** (%): The Sky Savings Rate currently set, from sUSDS ssr() at the latest block, as a yearly rate. - **sUSDS paid, 30 days** (%): What sUSDS actually paid over the last 30 days, from growth in chi() between two pinned blocks, annualized. - **USDS in sUSDS** (USDS): USDS deposited in sUSDS on Ethereum, from its totalAssets() at the latest day-end block. - **DAI Savings Rate** (%): The DAI Savings Rate currently set, from the Pot's dsr(), for comparison with the Sky Savings Rate. - **Savings rates by day** (%): The Sky Savings Rate and the DAI Savings Rate by day, with each governance change marked at its block. ### Supply and backing USDS and DAI supply by chain, what backs them and SKY purchases. - **USDS supply** (USDS): USDS supply on the selected chain at the latest day-end block, from totalSupply(). - **DAI supply** (DAI): DAI supply on the selected chain at the same block, from totalSupply(). - **USDS and DAI by chain** (USDS): USDS and DAI supply by day, split by chain, with bridged copies shown on the chain they live on. - **What backs USDS and DAI** (USD): Vat debt by collateral type, peg stability module holdings and allocator lines drawn, each as its own block, at the latest day-end block. - **SKY bought with surplus** (USDS): USDS spent by the Smart Burn Engine on SKY by day, with the SKY received in each purchase. Filters: Period (Last 30, 90 or 365 days); Chain (Ethereum or any chain USDS is bridged to). ## How it will be measured - The savings rate is sUSDS ssr(), a per-second rate in ray units compounded to a yearly figure; each change is read from the contract's File events and marked on the history. - Realized sUSDS yield is the growth of chi() between two pinned blocks, annualized, which captures every rate change in between; the DAI Savings Rate uses the Pot's dsr() and chi() the same way. - USDS and DAI supply are totalSupply() at each day's last block on each chain, with bridged copies kept apart from Ethereum supply; USDS held as sUSDS is sUSDS totalAssets(). - Backing is read from the Vat: each collateral type's Art times its rate gives its debt, while the peg stability module's stablecoins and each allocator's drawn line are shown as their own lines. - Smart Burn Engine purchases come from the flapper's transactions, with the USDS spent and the SKY received in each one. ## Data it needs - `stablecoin_supply_daily` (published): Native supply of each USD and EUR stablecoin on each covered chain at the chain's last block of each day, from totalSupply() reads, with bridged copies kept apart. - `yield_rates_daily` (to build): Supply rates, staking yields and vault share-price growth per pool and vault per day, in one comparable table. - `lending_markets_daily` (to build): Supply, borrow, utilization and rates per lending market (Aave, Morpho, Spark, Compound, Euler and others) at day end. - `protocol_revenue_daily` (to build): Fees users paid to each protocol and the part kept by the protocol or its token holders, per protocol and day, including buybacks. - `treasury_balances_daily` (to build): Balances of DAO, protocol and multisig treasuries per asset at day end, and their inflows and outflows. - Source: sUSDS ssr(), chi(), rho() and totalAssets() at day-end blocks on Ethereum, with its File events - Source: Pot dsr(), chi() and Pie() for the DAI Savings Rate - Source: USDS and DAI totalSupply() on each chain, and the DAI to USDS converter's events - Source: Vat ilks(ilk) Art and rate for every collateral type, including allocator vaults - Source: Peg stability module stablecoin balances and swap events - Source: Smart Burn Engine flapper transactions: USDS spent and SKY bought - Source: The Vow's surplus, its Vat dai balance minus its sin, against the buffer ## Questions ### What is the Sky Savings Rate? The Sky Savings Rate, or SSR, is the rate Sky governance pays on USDS deposited into sUSDS. Governance votes set it and can change it at any time, so the dashboard shows both the rate currently set and what sUSDS actually paid over recent periods. ### What is the difference between USDS and DAI? USDS is the stablecoin Sky introduced in 2024, and DAI is the original Maker stablecoin. Both are issued by the same protocol against the same balance sheet, and a converter contract swaps one for the other at a fixed one-to-one rate in either direction. ### How does sUSDS earn yield? sUSDS is a vault token. The number of tokens a holder has stays the same, while the USDS each token redeems for grows with the accumulator chi. Withdrawing returns the deposit plus the interest accrued since it was made, with no lockup. ### Is the DAI Savings Rate the same as the Sky Savings Rate? No. DAI holders earn the DAI Savings Rate through the Pot contract and sDAI, while USDS holders earn the Sky Savings Rate through sUSDS. Governance sets them separately, so the dashboard reads both and shows the gap between them. ### What backs USDS? Loans drawn against crypto collateral in the Vat, stablecoins held in the peg stability module and lines extended to Sky's allocators, which place funds in lending markets and tokenized treasuries. The backing page shows each source and its share of the total. ### What is the Smart Burn Engine? The mechanism that spends protocol surplus above a buffer set by governance on SKY bought in the market. Each purchase is a transaction, so the dashboard lists them with the USDS spent and the SKY received. ## Glossary - **sUSDS**: Sky's savings token: a vault that holds USDS and grows in value at the Sky Savings Rate. - **chi**: The rate accumulator in sUSDS and the Pot: how much one unit deposited at the start has grown to. - **Vat**: Sky's core accounting contract, which records collateral, debt and the internal balances behind USDS and DAI. - **Peg stability module**: A contract that swaps USDS or DAI one to one with a stablecoin such as USDC and keeps the stablecoin as backing. ## Related apps - [Yield-Bearing Stablecoins Compared: APY and Supply](https://voltfincrypto.com/apps/yield-bearing-stablecoins-compared) - [Stablecoin Lending Rates: USDC and USDT APY](https://voltfincrypto.com/apps/stablecoin-lending-rates) - [CDP Stablecoins: GHO, crvUSD and BOLD Supply](https://voltfincrypto.com/apps/cdp-stablecoins-gho-crvusd-bold) - [Stablecoin Market Share by Issuer](https://voltfincrypto.com/apps/stablecoin-market-share-by-issuer) - [Ethena USDe Supply and sUSDe Yield](https://voltfincrypto.com/apps/ethena-usde-supply-susde-yield) - [Stablecoin Market Cap and Total Supply](https://voltfincrypto.com/apps/stablecoin-market-cap) Build it in Voltfin Studio: https://app.voltfincrypto.com/signup?next=%2F