You may receive the “Excel found unreadable content in filename.xlsx” error when opening the Excel file. This error usually occurs if the Excel file is corrupted. However, there might be several other reasons that may cause this error. Let’s discuss the causes behind the error and the solutions to resolve it.

A speedometer, dial, or gauge chart displays a single value (usually displayed as an arrow) on a colored or sectored dial. The speedometer dial can be a half or a whole circle (the simplest option) or a sector located symmetrically vertically:

Scroll charts are often created to view detailed information for a small data range from a large dataset. For example, it is convenient to view weekly changes over a longer period of time, such as several months. Depending on the selected scroll step, you can view changes daily or weekly by moving the scroll bar.

The Scroll chart shows data for a long period in small scrollable time chunks. It makes easier to analyze data over a sufficiently long period in Microsoft Excel, Word or PowerPoint.
The Scroll chart displays some contiguous range of data from a large dataset. Using the provided Control tools, it is possible to add a scroll bar to the chart area and view the desired data range:

Sometimes you want to show a single chart with a series of different chart types. These charts containing data series with different chart types for each of them (lines, columns, areas, scatter, etc.) are called combo or combination charts:

If you want to combine more than two different data series with common horizontal and different vertical values, you could not just add another axis to the chart. You need to combine several charts into one chart.

Sometimes you want to show several axes in one chart to demonstrate each data series with different formatting and with different axis in one chart.

Pie charts are often used to present various kinds of data. You can create a pie chart in Excel that looks like the ones in popular glossy magazines. In addition, using 3D effects, you can display even not very presentable data colorfully and profitably.

Excel pie charts are useful for presenting parts of a whole by splitting a circle into sections. Each section looks like a slice of a pie and represents a category. Such a layout makes it easy to observe relationships between the parts, but the smaller the slice becomes (less than 10%), the more difficult it is to estimate visually.

The pie and donut (in Excel, doughnut) charts are widely used to present multiple parts of something whole. Using any of these chart types in Excel, you can demonstrate each part in one chart keeping their proportions. You can also represent the changes in those parts using a doughnut chart: