> For the complete documentation index, see [llms.txt](https://docs.stakingrewards.com/staking-data/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.stakingrewards.com/staking-data/methodologies/polkadot-pattern-substrate-srb/stafi-srb.md).

# StaFi SRB

Learn how StaFi staking rewards are calculated. FISSRB uses the Substrate era-based reward model with era validator rewards and total staked FIS tokens.

FISSRB is a benchmark representing the annualized staking rate for the FIS token.

FISSRB is calculated and published by Staking Rewards via the [StaFi Profile](https://www.stakingrewards.com/asset/stafi-protocol) and [Data API](https://www.stakingrewards.com/data-api).

> **TL;DR:** StaFi staking rewards use the Substrate era-based reward model: era validator rewards annualized over 365 days divided by total staked FIS tokens. Validator-level rates are adjusted by commission in the Nominated Proof of Stake system.

### FIS Staking Rewards Rate: FISSRB

$$
FISSRB = evr \* t\_y / st
$$

<table><thead><tr><th width="145">Formula Key</th><th width="169">Metric Name</th><th>Description</th></tr></thead><tbody><tr><td>evr</td><td>Era Validator Reward</td><td>The total reward distributed to all validators for the previous era, sourced directly from on-chain storage.</td></tr><tr><td>st</td><td>Staked Tokens</td><td>The total staked FIS in the active era, sourced from on-chain era total stake.</td></tr><tr><td><span class="math">t_y</span></td><td>Year Constant</td><td>365 eras — used to annualize the per-era reward (24-hour eras).</td></tr></tbody></table>

* FISSRB is non-compounded, excluding returns from reinvestment of rewards.
* The reward rate is derived from actual on-chain era rewards, not from an inflation model estimate.
* Both claimed and unclaimed rewards are included.

#### Slashing

* FISSRB does not factor in the possibility of slashing occurrences.
* StaFi implements Substrate's standard slashing mechanism. Validators can be slashed for equivocation or prolonged unresponsiveness.

***

### FIS Validator Staking Rewards Rate: FISSRB(v)

Staking Rewards calculates the FISSRB for each validator based on their individual era points (performance) and commission rate.

$$
FISSRB(v) = (vep / tep \* tvr) / t\_m \* t\_y / vst \* (1 - c)
$$

<table><thead><tr><th width="149">Formula key</th><th width="216">Metric Name</th><th>Description</th></tr></thead><tbody><tr><td><span class="math">vep</span></td><td>Validator Era Points</td><td>Validator era points accumulated in the observation period.</td></tr><tr><td>tep</td><td>Total Era Points</td><td>Total era points for all validators in the observation period.</td></tr><tr><td>tvr</td><td>Total Validator Rewards</td><td>All rewards distributed to all validators in the observation period.</td></tr><tr><td>vst</td><td>Validator Staked Tokens</td><td>Validator staked tokens, self-staked and delegated.</td></tr><tr><td><span class="math">t_y</span></td><td>Year Constant</td><td>365d</td></tr><tr><td><span class="math">t_m</span></td><td>Month Constant</td><td>30d</td></tr><tr><td><span class="math">c</span></td><td>Commission</td><td>Validator commission rate.</td></tr></tbody></table>

***

#### Observation Period:

1. The FISSRB is determined based on the latest completed era at the evaluation point.
2. This data is then annualized for a comprehensive year-long projection.

#### Calculation

The calculation happens every 6 hours and is immediately published via [Data API](https://www.stakingrewards.com/data-api).

#### Limitations

1. FISSRB employs a 365-day convention for annualizing era reward data. This convention remains consistent and does not accommodate adjustments for leap years.

***

### FIS Real Reward Rate: FISSRB^R

The real reward rate calculates the reward rate adjusted for inflation in the network.

$$
FISSRB^R = 1+FISSRB/(1+ir)-1
$$

<table><thead><tr><th width="147">Formula key</th><th width="148">Metric name</th><th>Description</th></tr></thead><tbody><tr><td>ir</td><td>Inflation Rate</td><td>Derived from on-chain era rewards: <code>eraValidatorReward * 365 / totalSupply</code>.</td></tr></tbody></table>

**Inflation Rate Behavior**

* StaFi's inflation rate is derived from actual on-chain era rewards. The protocol uses Substrate's NPoS staking model with 24-hour eras, distributing rewards to validators and nominators proportionally to their stake.

***

### Other StaFi metrics calculated by Staking Rewards:

<table><thead><tr><th width="212.99999999999994">Metric</th><th>Description</th></tr></thead><tbody><tr><td>Delegated Tokens</td><td>The number of FIS tokens delegated to validators.</td></tr><tr><td>Self Staked Tokens</td><td>The number of FIS tokens staked by validators directly.</td></tr><tr><td>Staking Wallets</td><td>Total number of nominators on-chain.</td></tr></tbody></table>

***

Data Sources:

* StaFi Substrate RPC (on-chain staking pallet queries via py-substrate-interface)
* CoinGecko for price and circulating supply

***

#### References:

* [StaFi Documentation](https://docs.stafi.io/)

***

:books: [Learn more about FIS Staking](https://www.stakingrewards.com/asset/stafi-protocol)

:bar\_chart: [Calculate your FIS Staking Rewards](https://www.stakingrewards.com/calculator?asset=stafi-protocol)

:gear: [Access historic StaFi Staking Data via API](https://www.stakingrewards.com/data-api)

```
Last updated on 03/16/2026
```