XSLT - if first element of splitting by empty space > 0, show empty cell

In my xml, the column where position()=3 can have these kind of values:

0.00 asg
0,34 dgfg
16.34 assfsf
334,77 sfsdf

So basicaly it has a float number with 2 decimals, an empty space and a string. WHat I need to do is this: if the number is 0 (so 0, 0.00 or 0,00) then show an empty cell. If it's larger than 0, don't change anything.

Here's what I tried:

<xsl:template match="cell[position()=3]" priority="7">
    <xsl:param name="text" select="."/>
    <xsl:variable name="newtext" select="concat(normalize-space($text), ' ')" />
    <xsl:variable name="perValue" select="substring-before($newtext, ' ')" />
    <xsl:variable name="perInt" select='format-number($perValue, "#")'/>
    <id><xsl:value-of select="perInt" /></id>
    <xsl:choose>
      <xsl:when test="perInt='0'">
        <td style="border:1px solid #d6d6d6;">
          <div>
            ...
          </div>
        </td>
      </xsl:when>
    </xsl:choose>
  </xsl:template>

But it doesnt work. The value of the column is 0.00 sdfdf and it is shown. When the value is >0 it works, the correct value is shown.