How to express in two or three letters how a column is to be sorted

On a just-now-coming-alive web page, I have two columns: change and change-percent. In the headers of the two columns, I want to give the user a small control so he can toggle between sorting the columns by abs value; and arithmetically.

In the first case, I can show him something like:

 +-----+    +-开发者_Python百科----+
 | ABS | or | MAG |
 +-----+    +-----+

What two- or three-letter abbrev can I give him to select sorting by signed value?

Or what graphics can I use to express the same ideas clearly and with good affordance?

Thanks!

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Regardless of where this question ends up :p, here's a suggestion.

I think ABS and MAG are decent keywords you can link to control sorting, especially if you have mouse-over text pop up that explains the action - i.e. "Sort by absolute value". You do have a nice setup with your icons though, and we should work to preserve that.

Currently, you have icons that you click to control highlighting and sort order (asc/desc)

I think that you should separate them a bit, and enhance the sort order with an absolute value modifier. By clicking the word 'abs', you might highlight the word (to show that it's active) and toggle between sorting regardless of sign. Here's my prototype:

Cheers