Entries in tables, such as row header text, should be short, or they can present difficulties. For example, long headers could make it harder for our eyes to follow a row with short entries but wide skips. One approach to adding the necessary details while keeping the table itself short and crisp is using footnotes.
Instead of placing the notes at the foot of the page, it's a good idea to add the notes directly at the foot of the table. We also call them table notes. Some benefits of this are as follows: