Display Text Over SVG Element On Hover

So I have a simple SVG element (copied below), and I want to display text (currently within the data-label attribute) when the rectangle with the bar class is hovered over.

<svg width="511" height="15">
    <rect fill="#555555" height="15" stroke="#000000" width="510"></rect>
    <rect class="bar" x="2" y="2" width="434" height="11" fill="#97C115" data-label="Test-Label"></rect>
</svg>

There could be any number of rectangles in the SVG and the label could say anything.

Since in my situation, the entire SVG element is created in JavaScript and then printed to a HTML environment, I am able to move the label anywhere. I just want the label to appear over the rectangle or above it when hovered.

Is this at all possible, since you cannot include text within the <rect> element?