# Stacked Bar Charts

Stacked bar charts break down and compare parts of a whole across different categories by stacking bars. Each bar shows the total, while segments within the bar show the composition of that total.

## When to use Stacked Bar Charts

Stacked bar charts are ideal when you want to:

* Show part-to-whole relationships across categories
* Compare both total values AND their composition
* Display how different components contribute to a total
* Track changes in composition over time

## Configuring Your Stacked Bar Chart

### Setting the X-Axis

The X-Axis represents your main categories or time periods that you want to compare:

**Best practices for X-Axis:**

* **Date fields for time periods**: Select a date field (like "Created Date" or "Order Date"), then group by Month, Quarter, or Year (to show composition changes over time)
* **Categories**: Department, Region, Product Line
* **Groups**: Customer Type, Project Phase, Priority Level

{% hint style="info" %}
**Using date fields:** Select an actual date field (like "Created Date"), then choose how to group the dates: **Year**, **Quarter**, or **Month**. Noloco automatically sorts dates chronologically (oldest to newest, left to right). You don't need a separate "Month" or "Year" field in your data.
{% endhint %}

**Example:** For showing ticket composition by month, set your X-Axis to "Created Date" and group by "Month".

### Adding Series (Y-Axis Values)

In stacked bar charts, each series becomes a segment within the bar. All series stack on top of each other to show the total.

**Key concept**: Each series typically represents a different category or type that makes up your total. For example:

* Different product types contributing to total sales
* Different ticket statuses making up total tickets
* Different expense categories in total spending

**For each series, you'll configure:**

1. **Y-Axis Value**: The numeric field to measure
2. **Aggregation Method**: How to calculate each segment
   * **Sum**: Total value for this segment
   * **Count**: Number of records in this segment
   * **Average**: Mean value for this segment
3. **Series Label**: Name of this component/segment
4. **Filter** (important!): Filter each series to only show the specific category it represents

### Example Configuration

**Scenario**: Show support tickets by status across months

**X-Axis Configuration:**

* Field: `Created Date`
* Group by: `Month`

**Series 1:**

* Label: "Open"
* Y-Axis Value: (Record count)
* Aggregation: `Count`
* Filter: Status equals "Open"

**Series 2:**

* Label: "In Progress"
* Y-Axis Value: (Record count)
* Aggregation: `Count`
* Filter: Status equals "In Progress"

**Series 3:**

* Label: "Closed"
* Y-Axis Value: (Record count)
* Aggregation: `Count`
* Filter: Status equals "Closed"

This creates a stacked bar chart where each month's bar shows the total tickets, broken down by status.

## How Series Filters Work

The key to stacked bar charts is using filters on each series:

1. Each series shows data from the same table
2. Apply a filter to each series to isolate a specific category
3. The filters should be mutually exclusive (no overlap)
4. Together, all series should represent the complete dataset

**Example Pattern:**

* Series 1 Filter: `Priority = "High"`
* Series 2 Filter: `Priority = "Medium"`
* Series 3 Filter: `Priority = "Low"`

## Common Use Cases

### Sales Composition by Product Category

* **X-Axis**: Order Date (grouped by Month)
* **Series 1**: Electronics Sales (filtered to Category = "Electronics")
* **Series 2**: Clothing Sales (filtered to Category = "Clothing")
* **Series 3**: Home Goods Sales (filtered to Category = "Home Goods")

### Budget vs. Actual Spending by Department

* **X-Axis**: Department
* **Series 1**: Allocated Budget (Sum of Budget field)
* **Series 2**: Actual Spending (Sum of Spent field)

### Ticket Distribution Over Time

* **X-Axis**: Created Date (grouped by Week)
* **Series**: One for each ticket status (Open, In Progress, Closed, etc.)

### Revenue by Customer Type

* **X-Axis**: Sale Date (grouped by Quarter)
* **Series 1**: Enterprise Revenue (filtered to Type = "Enterprise")
* **Series 2**: SMB Revenue (filtered to Type = "SMB")
* **Series 3**: Individual Revenue (filtered to Type = "Individual")

## Tips for Better Stacked Bar Charts

1. **Limit series count**: 3-6 series work best. Too many segments become hard to read
2. **Use logical ordering**: Stack series in a meaningful order (e.g., sequential stages, priority levels)
3. **Consistent colors**: Keep the same series in the same color position across all bars
4. **Filter properly**: Ensure your series filters don't overlap or leave gaps
5. **Consider alternatives**: If you want to compare totals across categories rather than composition, use a regular bar chart instead
6. **Add context**: Use titles and subtitles to explain what the stacks represent

## 100% Stacked Bar Charts

Some stacked bar charts can show percentages instead of absolute values:

* Useful when you want to compare proportions rather than totals
* All bars reach 100%, showing relative composition
* Great for seeing how the mix changes even if totals vary