Use thetable, which gives the total amounts of sales(in millions ofdollars) foraerobic, basketball,cross-training, and walking shoes for the years2005-2011. Determine which type of shoe shows greatervariation: aerobic orcross-training.

Cross- Year Aerobic Basketball Training Walking 2005 249 878 1476 3673 2006 250 964 1538 4091 2007 276 892 1562 4197 2008 254 718 1635 4204 2009 217 741 2065 4416 2010 247 721 2109 4256 2011 252 729 2157 4299