XLST IF Condition not working in Sharepoint designer

I am completely novice in SharePoint designer. if I pass the value to my if condition, I am getting the below error

Failed setting processor stylesheet : 0x80004005 : Expected token 'EOF' found 'NUMBER'. @Month=Jan -->18<--

</xsl:if>
<xsl:if test="@Month=Jan 18">
<td class="ms-vb"><xsl:value-of select="sum(/dsQueryResponse/Rows/Row/@No_x0020__x0027_of_x0020_Instanc)" /> 
</td> </xsl:if>
</tr></xsl:template>

Can anyone guide me to fix this issue?