A cross-section data shows information about different subjects or elements of a sample or population during the same period of time.
The table below shows cross-section data for the following two reasons:
First, you can see that the subjects are different since the information was compiled for 5 different companies.
Second, the information was compiled during the same time period. It was during the year of 2001.
In summary, a set of data is a cross-section data whenever the following two conditions are met.