# What are pivot tables, and how can they be helpful in analyzing data?

What are pivot tables, and how can they be helpful in analyzing data?

A pivot-table is a tool to dynamically show a slice and group multivariate data in tabular form.

For example, when we have the following data structure

Region  Year  Product  Sales
US      2008  Phones   125
EU      2008  Phones   352
US      2008  Mouses   52
EU      2008  Mouses   65
US      2009  Phones   140
EU      2009  Phones   320
US      2009  Mouses   60
EU      2009  Mouses   100


A pivot table can for example display a table with the sum of all products with in the rows the years and in the columns the regions.

All dimensions of the table can be switched easily. Also the data fields shown can be changed. This is called pivoting.

The tool is useful in exploratory data analyses. Because it is a dynamic tool, it can be used to visually detect patterns and outliers etc.

Most spreadsheet applications have support for this kind of tables.

An image from wikipedia:

• Note that in the business intelligence world this is also known as OLAP or Online Analytical Processing or Cubes. – StatsStudent Nov 4 '15 at 5:50