At the CTS website?

What does the RD stand for at the CTS website?

Right now mine is 19.6

anybody know?

if you look at your profile you'll see the RD

It stands for 'rating deviation'. The lower it is, the more accurate your rating is considered to be. When you start out, it's high and your rating changes more rapidly. When you do a lot of problems and it gets to be low, your rating doesn't change as quickly.

From http://chess.emrald.net/ratinginfo.php :

"The Ratings Deviation is used to measure how much a tactician's current rating should be trusted. A high RD indicates that the tactician may not be competing frequently or that the tactician has not solved very many problems yet at the current rating level. A low RD indicates that the tactician's rating is fairly well established. This is described in more detail below under RD Interpretation."
...

thanks guys.