The following table shows the total revenue (in billions of $) for Walmart Stores, Inc. and Target

Question:

The following table shows the total revenue (in billions of $) for Walmart Stores, Inc. and Target Corp. for the years 2008-2010.
Year...........2008..........2009..........2010
Walmart......379.8.........404.3.........408.2
Target.........63.4............65.0..........65.3
Source: Annual Reports of Walmart Stores, Inc., and Target Corp.
a. Calculate the average growth rate for each firm.
b. Which firm had the higher growth rate over the 2008-2010 period?