Answer
See the graph.
Work Step by Step
The height of the first bar (2001): $1.46-0.70=0.76$
The height of the second bar (2011): $3.83-0.70=3.13$
$\frac{the~height~of~the~second~bar}{the~height~of~the~first~bar}=\frac{3.13}{0.76}\approx4.1$