In the diagram shown, what is the ratio of shaded parts to unshaded parts?

6 unshaded squares and 9 shaded squares.
For every 2 shaded parts there are 3 unshaded parts.
For every 9 shaded parts there are 2 unshaded parts.
For every 3 shaded parts there are 6 unshaded parts.
For every 3 shaded parts there are 2 unshaded parts.