This question has two parts, each requiring you to read specific values from the graph and perform a calculation. Let me walk through both.
Dropdown 1: Percent decrease in sales from 2007 to 2009Look at the blue bars (Sales, left y-axis):
-
2007 sales: approximately
$18M (the tallest bar on the graph)
-
2009 sales: approximately
$9MPercent decrease = (Old - New) / Old x 100= (
18 -
9) /
18 x
100=
9 /
18 x
100=
50%Answer: 50Dropdown 2: Increase in dollar sales per unique visitor from 2002 to 2007Here you need values from BOTH the bars and the line. Read Sales from the blue bars (left axis) and Traffic from the gold line (right axis).
For 2002:- Sales ≈
$6M- Traffic ≈
12M visitors
- Sales per visitor =
$6M /
12M =
$0.50For 2007:- Sales ≈
$18M- Traffic ≈
18M visitors
- Sales per visitor =
$18M /
18M =
$1.00Increase =
$1.00 -
$0.50 =
$0.50Answer: 0.5Key Insight: The
key trap in Dropdown
2 is that you must read TWO different scales carefully — the left axis for the bars and the right axis for the line — and then compute a ratio before finding the difference. Many students either misread the traffic axis or forget to calculate the per-visitor rate for each year separately before subtracting.