# Performance

## Time-Weighted Return (TWR)

The API provides **Time-Weighted Return (TWR)** for portfolio performance. TWR measures how the investments themselves have performed, independent of the timing and size of deposits and withdrawals — consistent with how fund factsheets report returns.

For the full methodology — including formulas, Money-Weighted Return (MWR), and when to use each — see [Performance Calculations](/guides/fondo-wiki/performance-calculations).

## Get account performance

Returns an array of daily performance entries for the account. Each entry contains the `date` and the `dayReturn` — the daily return expressed as a decimal.

```json
{
  "$ref": "#/components/schemas/performance_entry",
  "components": {
    "schemas": {
      "performance_entry": {
        "$id": "/models/performance/performance_entry.yaml",
        "type": "object",
        "required": [
          "date",
          "dayReturn",
          "dayResult",
          "cumulativeReturn"
        ],
        "properties": {
          "date": {
            "type": "string",
            "format": "date",
            "description": "The date of the performance entry.",
            "example": "2025-01-02"
          },
          "dayReturn": {
            "type": "number",
            "description": "The daily return as a decimal (e.g. 0.0032 = 0.32%).",
            "example": 0.0032
          },
          "dayResult": {
            "type": "number",
            "description": "The absolute SEK profit/loss for the day\n",
            "example": 120.12
          },
          "cumulativeReturn": {
            "type": "number",
            "example": -0.01,
            "description": "Cumulative return since account inception as a fraction (e.g. 0.05 means +5%)\n"
          }
        }
      }
    }
  }
}
```

## Date filtering

By default the endpoint returns the full performance history. To limit to a specific range, pass both `start` and `end` as ISO 8601 date query parameters (e.g. `?start=2025-01-01&end=2025-03-01`). Both must be provided together.

## Cumulative returns

Documentation for cumulative returns is **coming soon**.