Center text in SVG rect -- horz and vert

• text element in a sibling to rect.
• left side of text element positioned at horz center of rectangle and vertical center
• text-anchor for centering text horizontally
• alignment-baseline for centering vertically

<svg height="50" width="200">
  <rect fill="green" x="0" y="0" width="200" height="50"></rect>
  <text x="100" y="25" fill="red" text-anchor="middle" alignment-baseline="central">Christmas Time!</text>
</svg>

see jsbin