I am looking for some clarification on the relationship between numbers entered in the section of Designer for Plot area and the overall dimensions of the chart as set on the General tab for width and height.

Here's how I see it so someone can confirm or correct my interpretation of what’s going on.
If I use the term "chart area" I am referring to the total area that will be taken by the charting applet is called/displayed.
The plot area is the area of the chart itself inside the chart area.
The documentation states that the range for the values in the plot area is 0-1.
Is this a scale or an actual measurement?

With the default values for the plot area, the actual chart elements appear to center themselves within the total chart area.
MY first question is what determines the ratio between the total plot area and the total chart area and what are the actual default values
Changing the value to 1 for the top value, the plot area then expands towards the top of the total chart area.
I would then assume this value extends the plot area to the maximum allowed area with the chart area.
I then am assuming that the value used for the bottom parameter to extend to its farthest point of the chart area, would be the inverse or 0.

The maximum values also cause the labels for the axis's to be covered by the plot area.

Any assistance would be greatly appreciated