Excel Tables make analyzing data, a breeze. It surprises me that it is not used as often as it should. It automatically “includes” new data you add to your spreadsheets, it automatically drags down formulas for you, it automatically formats the tables for you. In addition to that, you can use structured references that make your formulas tractable without having to name each range. You can also link an Excel Table to your PowerPivot Model. For a comprehensive, yet concise list of stuff excel tables can do, I recommend reading through this page.