A (somewhat blunt) rule of thumb, not just for you, but for anyone in this endeavor: In the future, if you are making a graph like this, and the differences ar

A (somewhat blunt) rule of thumb, not just for you, but for anyone in this endeavor: In the future, if you are making a graph like this, and the differences are so small that they don't show up when your y-axis starts at 0, they probably aren't important enough to talk about. If you've taken a stats class, you probably know there are times when small differences are meaningful. Any time you're analyzing your own data, though, these differences are rarely worth even considering. Taking a survey and analyzing the resulting data is very hard. There are countless nuances that can affect your results, both mathematical and psychological. Look at political polling - even the people who do it for a living regularly get things wrong.