Do you need a label on each line in an array of entries? No.
should you label each line in an array of entries?
Who are your users? Does it mean data entry people or grandparents? How often do they do it? How fast are they needed (or strongly encouraged) to do it?
It depends on the context of the user.
If you are dealing with people who work with this product on a daily basis, they must know which column represents which data point. Labels can actually hinder – especially if users visually analyze the data.
Is it basically a spreadsheet? If this is the case and the users understand it well, they will expect it to behave like a spreadsheet. Who do not have labels on each field entry.
If you are dealing with people who are not necessarily familiar with your system, or who may have trouble digitizing data, or who use your application only occasionally, you are now starting to consider the addition of labels.