> For the complete documentation index, see [llms.txt](https://docs.powerpointgeneratorapi.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.powerpointgeneratorapi.com/examples/chart/additional-data.md).

# Additional data

1. Select the shape by `name` you want to modify. See [here](/knowledge-base/finding-shape-names.md) to find shape names.
2. Use `additional_data` to insert custom values directly into specific cells. 
3. Each `cell_target` defines the starting cell where the data will be written.
4. `Additional_data` is not tied to the chart’s data range, so you can add data anywhere. It's useful for when you want to add helper values, metadata, or computed fields without affecting the main chart series.

Reference: [chart](/json-template-syntax/shapes/chart.md)

Download: [input.zip](https://drive.google.com/uc?export=download\&id=1RjhuXp3a-I531dgZBia3_80O6akhWQO8) | [output.pptx](https://drive.google.com/uc?export=download\&id=1CynZMM_5aPHuI4wjGAwVTCm1hwSkNtAC)

{% columns %}
{% column width="41.66666666666667%" %}

<figure><img src="/files/rPdVQEprnXvtRB7TjIMn" alt=""><figcaption></figcaption></figure>

***

<figure><img src="/files/aXwABXDyrQVbv0qY6wST" alt=""><figcaption></figcaption></figure>
{% endcolumn %}

{% column width="58.33333333333333%" %}
{% code lineNumbers="true" %}

```json
{
    "presentation": {
        "template": "template.pptx",
        "slides": [
            {
                "slide_index": 0,
                "shapes": [
                    {
                        "name": "Chart 5",
                        "additional_data": [
                            {
                                "cell_target": "B22",
                                "data": [
                                    [
                                        0.2,
                                        0.3,
                                        0.35
                                    ],
                                    [
                                        0.4,
                                        0.5,
                                        "0.45%"
                                    ]
                                ]
                            },
                            {
                                "cell_target": "A2",
                                "data": [
                                    [
                                        " ",
                                        35,
                                        0.6
                                    ],
                                    [
                                        "maj",
                                        0.5,
                                        58
                                    ]
                                ]
                            },
                            {
                                "cell_target": "A4",
                                "data": [
                                    [
                                        "Category 3",
                                        5,
                                        10
                                    ]
                                ]
                            },
                            {
                                "cell_target": "AA5",
                                "data": [
                                    [
                                        0.5,
                                        0.2
                                    ],
                                    [
                                        0.455,
                                        0.7234
                                    ]
                                ]
                            }
                        ]
                    }
                ]
            }
        ]
    }
}
```

{% endcode %}
{% endcolumn %}
{% endcolumns %}