I have a series of values that are percentages of a whole
For example:
- 10 %
- 8 %
- 17 %
- 14 %
- 12 %
- 19 %
- 16 %
These are plotted on a bar graph with the top scale being 100%. As you can see there is lots of wasted space so I thought that it would be better to scale the values to take advantage of the space.
Can anyone suggest a mathematical formula I could use to scale the values into a new set of values based on a 0 to 100 scale. I would assume the largest value (e.g. 19% in this case) becomes the new 100% value.

Usually you just make the left axis run from $0\%$ to the maximum or some round number a little above the maximum. In your case, from $0\%$ to $20\%$ seems reasonable. You could multitply by $\frac {100}{max value}$ but it wouldn't be percent any more.