Begin-Block

Minting parameters are recalculated and inflation paid at the beginning of each block.

Inflation rate calculation

Inflation rate is calculated using an "inflation calculation function" that's passed to the NewAppModule function. If no function is passed, then the SDK's default inflation function will be used (NextInflationRate). In case a custom inflation calculation logic is needed, this can be achieved by defining and passing a function that matches InflationCalculationFn's signature.

Copy type InflationCalculationFn func(ctx sdk.Context, minter Minter, params Params, bondedRatio sdk.Dec) sdk.Dec

NextInflationRate

The target annual inflation rate is recalculated each block. The inflation is also subject to a rate change (positive or negative) depending on the distance from the desired ratio (67%). The maximum rate change possible is defined to be 13% per year, however the annual inflation is capped as between 7% and 20%.

Copy NextInflationRate(params Params, bondedRatio sdk.Dec) (inflation sdk.Dec) { inflationRateChangePerYear = (1 - bondedRatio/params.GoalBonded) * params.InflationRateChange inflationRateChange = inflationRateChangePerYear/blocksPerYr // increase the new annual inflation for this next cycle inflation += inflationRateChange if inflation > params.InflationMax { inflation = params.InflationMax } if inflation < params.InflationMin { inflation = params.InflationMin } return inflation }

NextAnnualProvisions

Calculate the annual provisions based on current total supply and inflation rate. This parameter is calculated once per block.

Copy NextAnnualProvisions(params Params, totalSupply sdk.Dec) (provisions sdk.Dec) { return Inflation * totalSupply

BlockProvision

Calculate the provisions generated for each block based on current annual provisions. The provisions are then minted by the mint module's ModuleMinterAccount and then transferred to the auth's FeeCollector ModuleAccount.

Copy BlockProvision(params Params) sdk.Coin { provisionAmt = AnnualProvisions/ params.BlocksPerYear return sdk.NewCoin(params.MintDenom, provisionAmt.Truncate())