you mean standard deviation?

try STDEV function

On Thu, 20 Mar 2008 16:36:00 -0700, mb wrote:

Please put your question in your message body. It gets truncated in many news
readers and you can give more information in a body.

For example, in my newsreader you are asking: "Does anyone know if excel has a
function to calculate standard er."

I'm no sure what an "er." is. I might guess "error" and that you are looking
for standard error, but I also know that had you typed "standard error" into
HELP, you would have gotten some information, so your question doesn't make
sense.
--ron