Penny,
The important things to note about Jon's example are:
(1) It is based on a 100% Stacked Bar Chart.
(2) The totals of each of the groups = 35.
(3) You need to work with numbers that add up to 35.
There are five series. The second and fourth series are given. The middle
series consists of the number 7. Since the middle series is used for spacing
only, the number 7 could be 8, 9, 10, 4, 3, etc. As you increase or decrease
that number the middle spacing will change. The only restriction is that
each point in this series must be exactly the same so that the tornado has a
vertical inside left and right borders.
The numbers for the first and fifth series are plugs to get the groups to
equal 35. The numbers in these series will need to be worked with so that
the outside left and right borders of the tornado chart are vertical.
Hope this helps.