The total value of a variable, such as sales figures for a product, over the course of the previous 12 months. This is a rolling yearly sum, so changes at the end of each month with data from the new month added to the total and data from the first month of the period taken away.
In simple word, it is last 12 month revenue / sales.
For Example, Feb 2014 to Jan 2015 sales are called MAT Feb 2015 sales.
MAT is for the past 12 month sales, comparing two points MAT data evens out the fluctuations.
MAT JAN 2014 = FEB-13+MAR-13+…..+DEC-13+JAN-14
MAT JUNE 2015 = JULY-2014+AUG-2014+……….+MAY-2015+JUNE-2015
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