One of the things I dislike about stacked area charts (or stacked bar charts) is that are in many cases are used to show percentage breakdown over time.
The problem with representing percentage breakdown over time this way is that it visually eliminates the size of the sample, be it size of market, number of users, page visits, etc. It is visually implying that the same size has stayed the same over time.
The first displays the percentage of market by manufacturer over time. In this chart, Apple's performance looks mediocre.
Then look at the second graph that displays the number of units shipped by manufacturer. Here the amazing growth of the smartphone market is visually captured along with the breakdown of which manufacturers are driving or benefiting from the growth.
Comments
One of the things I dislike about stacked area charts (or stacked bar charts) is that are in many cases are used to show percentage breakdown over time.
The problem with representing percentage breakdown over time this way is that it visually eliminates the size of the sample, be it size of market, number of users, page visits, etc. It is visually implying that the same size has stayed the same over time.
Take these two charts representing the breakdown of smartphone shipments by manufacturer: http://s831.us/1kmFK28 and http://s831.us/1kmFrEz
The first displays the percentage of market by manufacturer over time. In this chart, Apple's performance looks mediocre.
Then look at the second graph that displays the number of units shipped by manufacturer. Here the amazing growth of the smartphone market is visually captured along with the breakdown of which manufacturers are driving or benefiting from the growth.