The 2D Transformation node provides scale and translation parameters for the X- and Y-axes, but not the Z-axis. The Rotation parameter rotates around the Z-axis, or perpendicular to the object's surface.
Rotation - Accepts a Float node. Rotates around the Z-axis.
Scale - Accepts a Float node. Scales the X/Y axes.
Translation - Accepts a Float node. Translates the X/Y axes.