A sand chart is a type of data visualization that is essentially a line chart where the area under each line is filled in with a different color.
Understanding Sand Charts
Fundamentally, a sand chart builds upon the familiar structure of a line chart, but it adds an important visual dimension by coloring the space beneath each line. This distinctive feature helps in portraying not just the trend of individual data series over time, but also their relative magnitude or contribution.
As noted on February 6, 2018, sand charts are:
- Line charts with filled areas: They take the form of line graphs, but the space between the line and the baseline (or the previous line in a stacked context) is colored.
- Used for time series data: Their primary application is to visualize data that changes over a period, making trends and evolution clear.
- Flexible with normalization: They can display raw values or be normalized, often presented as percentages to show proportional contributions.
Key Characteristics
Sand charts possess several defining attributes that make them effective for specific analytical needs:
- Visual Foundation: They are directly derived from standard line charts, making them intuitively understandable for anyone familiar with basic graphing.
- Area Filling: The most distinguishing feature is the use of distinct colors to fill the area under each line, which enhances the visual impact and helps in differentiating categories.
- Time-Series Focus: They are particularly well-suited for depicting how different components or categories evolve over time.
- Normalization Option: Data can be presented in absolute values or scaled as percentages, allowing for analysis of either raw change or proportional change.
Practical Applications
Sand charts are highly effective in scenarios where you need to visualize how different parts contribute to a whole over time, or how multiple categories trend simultaneously.
Some common practical uses include:
- Market Share Analysis: Illustrating how the market share of various companies or products changes over quarters or years.
- Resource Allocation: Showing the distribution of a budget or resources across different departments or projects over time.
- Website Traffic Breakdown: Visualizing the proportion of traffic coming from different sources (e.g., organic, paid, social) each month.
- Demographic Shifts: Tracking changes in the age groups or population segments of a region over decades.
By visually separating and layering the filled areas, sand charts provide an immediate sense of not just individual trends but also the overall composition and its evolution, making complex time-series data more accessible and insightful.