How can I get sign for "Adjustment"?

How can I get sign for "Adjustment"?

Hi,

I try to get a tax and adjustment value from Zoho API.
( see below )

<FL val="Tax"><![CDATA[1412.5]]></FL>
<FL val="Adjustment"><![CDATA[0.5]]></FL>

On the web, I can select sign of adjustment. ( plus or minus )
But from API, I can't get this sign of adjustment.

I want to know which value -0.5 or +0.5











 How can I get which sign????