IPhone calendar app layout

When looking at the day view in my calendar, I notice that one of my calendar's events all line up on the left side. The fill the whole screen from left to right. When I add an event to a different calendar and it occurs at the same time, it causes each event from the different calendar to take up half of the space. So let's say a "red" calendar event is input first between 3-4 pm and it takes up the entire time from the left side where the times are to the far right side of my iphone screen. When I input a "green" calendar event between 3-4 pm, the original red event is shortened to half it's length and the green event looks as if it is indented and sits directly to the right of the red event. Even if the "green"event is 3:30-4:30 they both take up half the screen. That's great. I'm having problems when I add other "color" calendar events. Sometimes it "indents" an event and puts it 1/4, halfway, 3/4 of the way across my screen even when there is nothing else during that time period, or seems to indent different color calendar events randomly at different positions, breaking the left half of the screen into sixths instead of just lining the events up one under the other.

For example, the calendar puts the first "red" calendar on the right half of the screen, say at 3-4 pm. A different "green" event that starts at 3:30(-4:30 pm) rightfully takes up the opposite (left) side of the screen. But when I add another "red" 4-5 pm event which should go right below the "red" 3-4 pm event, it then squishes the "green" 3:30 event that was on the left side of the screen and puts BOTH the 3:30-4:30 "green" and 4:00-5:00 "red" event on the the left side of my screen instead of using any part of the open right half of the screen. Anyone have ideas about how it splits up the use of the screen into percentages? How does it decide in which order to indent calendar events?