Compare and rank
Slope chart
Connects category values across two or a few ordered positions to show change.
- Chart
- Change between points
- Comparison
What it answers
Which categories changed most between positions?
- Shape
- Lines between ordered positions
- What it shows
- Relative change and reordering.
Example: Skye Ascent Ltd
The question
Will Skye Ascent Ltd’s plan reach the board’s cost-per-launch target?
Skye Ascent Ltd cost per launch, 2025 to 2027
Skye Ascent Ltd is a fictional company created for Insyt.
The misleading version
Same question, drawn badly
Two end points hide a dip in between
What goes wrong. Only the end points are shown, so the low point of GBP 64.0 million in 2027 disappears. When the path matters, use a line chart.
When to use it
Use it when
Comparing two or a few snapshots.
Avoid it when
Many crossing lines or a need to show intervening fluctuations.
How to read it
Follow each labelled line between ordered columns and compare its slope/endpoints.
Note
Make position order explicit.
The data you need
- Layout
- Long table
- Fields
- Category or ordered position: text/date; Series: text; Value: number
- One row is
- One series value within one category or position. What is the grain?
- Rules
- Use one value per category-series pair after aggregation. Define category and series order.
- Optional
- Wide alternative: Category,North,South with one row per category.
- Preparation
- Aggregate one value per category-position pair; order positions explicitly and keep category identity stable.
- Units
- Use the measured variable's stated unit consistently. No denominator is implied unless the value is a rate or proportion.
Worked example
Data A:30 to 45; B:40 to 34. Join endpoints. A rises 15 and overtakes B, which falls 6.
| Category | Series | Value |
|---|---|---|
| A | North | 30 |
| A | South | 45 |
| B | North | 34 |
| B | South | 40 |