Answer
The sales increased the most between 2014 and 2015.
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The sales increased the least between 2013 and 2014.
Work Step by Step
greatest increase = largest slope.
$(14,182.20), (15, 233.72)$
$m_{1}=\frac{233.72-182.20}{15-14}= 51.52$
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least increase = smallest slope
$(13,170.91), (14, 182.20)$
$m_{2}=\frac{182.20-170.91}{14-13}= 11.29$
