# Yield Token

The YT ([Yield Token](https://dev.spectra.finance/glossary#yield-token)) represents the yield that is accrued by an [IBT](https://dev.spectra.finance/glossary#ibt) (Interest Bearing Token). It is created when an IBT or an underlying asset is deposited into a [PrincipalToken](https://dev.spectra.finance/technical-reference/contract-functions/principal-token), and the interest bearing token is split into [PT](https://dev.spectra.finance/glossary#principal-token) and [YT](https://dev.spectra.finance/glossary#yield-token).

The YT can be traded with other users to hedge or speculate on yields. A user holding a YT can claim his yield by calling [`claimYield`](https://dev.spectra.finance/technical-reference/principal-token#claimyield) or [`claimYieldInIBT`](https://dev.spectra.finance/technical-reference/principal-token#claimyieldinibt) on the Principal Token contract.

For more information, see [Tokenising Yield](https://dev.spectra.finance/guides/tokenizing-yield).

YT.sol code can be found on [GitHub](https://github.com/perspectivefi/spectra-core/blob/main/src/tokens/YieldToken.sol).

## Methods

### transfer

```solidity
function transfer(
    address to,
    uint256 value
) public returns (bool success)
```

Standard ERC20 `transfer` function with a pre-transfer yield update.

<table><thead><tr><th width="190.33333333333331">Input Parameter</th><th width="115">Type</th><th>Description</th></tr></thead><tbody><tr><td><code>to</code></td><td>address</td><td>The address to send the YT <code>to</code></td></tr><tr><td><code>value</code></td><td>uint256</td><td>The amount of the YT to send</td></tr></tbody></table>

<table><thead><tr><th width="189.33333333333331">Return Parameter</th><th width="121">Type</th><th>Description</th></tr></thead><tbody><tr><td><code>success</code></td><td>bool</td><td>A boolean value indicating whether the transfer was successful</td></tr></tbody></table>

### transferFrom

```solidity
function transferFrom(
    address from,
    address to,
    uint256 value
) public returns (bool success)
```

Standard ERC20 `transfer` function with a pre-transfer yield update.&#x20;

{% hint style="warning" %}
`from` must have previously approved `msg.sender` to transfer `value` using the standard ERC20 approval process.
{% endhint %}

<table><thead><tr><th width="190.33333333333331">Input Parameter</th><th width="115">Type</th><th>Description</th></tr></thead><tbody><tr><td><code>from</code></td><td>address</td><td>The address to send the YT <code>from</code></td></tr><tr><td><code>to</code></td><td>address</td><td>The address to send the YT <code>to</code></td></tr><tr><td><code>value</code></td><td>uint256</td><td>The amount of the YT to send</td></tr></tbody></table>

<table><thead><tr><th width="189.33333333333331">Return Parameter</th><th width="121">Type</th><th>Description</th></tr></thead><tbody><tr><td><code>success</code></td><td>bool</td><td>A boolean value indicating whether the transfer was successful</td></tr></tbody></table>

## View Methods

### getPT

```solidity
function getPT() public view returns (address)
```

Get the [Principal Token](https://dev.spectra.finance/technical-reference/contract-functions/principal-token) associated with the yield token.

### decimals

```solidity
function decimals() public view returns (uint8)
```

Returns the number of decimals of the YT (same as the PrincipalToken's decimals). See [`decimals()`](https://dev.spectra.finance/technical-reference/principal-token#decimals)

### balanceOf

```solidity
function balanceOf(address account) public view returns (uint256)
```

Returns the  balance of YT before[ expiry of the principal token](https://dev.spectra.finance/technical-reference/principal-token#maturity) and return 0 after the expiry of the principal token.&#x20;

### actualBalanceOf

```solidity
function actualBalanceOf(address account) public view returns (uint256)
```

Returns the real balance of YT as defined in the balanceOf from ERC20 standard&#x20;

i.e the sum of incoming YT to the `account` minus the outgoing balance of YT tokens.&#x20;