Hi and welcome back!
In this video, we’ll create the second chart,
which will be part of our dashboard – a
pie chart showing the percentage of the total
reviews that each audiobook obtained.
The number of reviews is quite important in
the marketplace we are studying, and this
is the reason why we are interested in finding
out which audiobooks collected more reviews.
An alternative visualization would be a pie
chart showing us the percentage of people
who purchased a given audiobook.
Ok.
Given that we know what we would like to accomplish,
things should be easier, right?
I’ll add the Rating field to the workspace
area.
The number we obtained is the sum of all ratings.
Let’s use “Count” for this measure.
Perfect.
The total number of reviews is 10,798, and
we know for a fact that this is true.
Let’s go ahead and add the audiobook names
dimension above the ratings field, shall we?
This creates a breakdown by audiobook.
Exactly what we want to have.
Now, I can simply select the pie chart icon
within the “Show me” functionality and
I’ll create a pie chart.
A really tiny one, but still a pie chart 
To increase the chart’s size, I can simply
click anywhere in the workspace area, hold
the Control key and then use the arrow keys.
If I press Control and Up, the chart grows
vertically, while Control and Right arrow
increase the chart’s size horizontally.
The opposite is true as well, we can decrease
the chart’s size by pressing Ctrl and Down
key or Ctrl and Left arrow.
Awesome 
What else?
We need labels, right?
Otherwise it is difficult to gain an idea
what portion of overall reviews a specific
audiobook accounted for.
I’ll drag the “Rating” field in “Label”
and the number of reviews appears right next
to each audiobook (again we need the Count
of ratings, and not the Sum).
Ok.
But how do we display these as a percentage?
That’s not that difficult actually.
All I have to do is go to “Analysis”,
select “Percentage of”, and then click
on “Table”.
Boom  Here we are.
These are the percentages each audiobook accounted
for among the total number of reviews.
The pie chart and the labels we added show
us that Audiobooks 1 and 2, account for more
that 50% of the total number of reviews the
company received.
Very interesting!
The business relies greatly on these best-sellers.
In our next lesson, we’ll create the third
and final chart that would allow us to complete
our initial plan and obtain the dashboard
we intended from the very beginning.
