A pivot table is a powerful tool in Excel that allows you to summarize, analyze, explore, and present summary data. It is used to transform columns into rows and rows into columns, and allows grouping by any field (column), and using advanced calculations on them. PivotTables work on a snapshot of your data, called the cache, so your actual data doesnt get altered in any way. PivotTables are especially useful with large amounts of data that would be time-consuming to calculate by hand. Some of the uses of a pivot table include:

• Calculating sums or averages in business situations
• Showing totals as a percentage of a whole
• Generating a list of unique values

To create a pivot table, you need to select the cells you want to create a PivotTable from, and then select Insert > PivotTable. The data should be organized in columns with a single header row, and each cell in subsequent rows should contain data appropriate to its column heading. Excel tables are already in list format and are good candidates for PivotTable source data. PivotTables can be used to answer questions like "How many sales did we get last week, month and year?". PivotTables are a dynamic table, so when you update your data, just hit refresh and your pivot table is updated with the new figures.