@Tư-Mã-Tần-Quảng
You could install the XML Tools plugin and use its XSLT Transformation feature.
Open Plugins Admin and install XML Tools plugin.
After Notepad++ has been restarted paste the XSLT code from below to an empty tab and save it for example as Transform.xsl.
Open the XML file you want to process.
Go to (menu) Plugins -> XML Tools -> XSLT Transformation.
In the dialog popping up click on the ellipsis button and in the file selector dialog popping up select the XSL file you created in step 2.
Click the Transform button.
A new document will be opened with your changes applied. Save it to the original file.
In the following the XSLT code to do your requested transformations. I guess you want to increase the value of the asalary, bsalary and msalary tags by a percentage value, thus I divided the factors you provided by 100.
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output
method="xml"
indent="yes"
encoding="utf-8"
omit-xml-declaration="no"
/>
<!-- Copy all nodes not affected by the rules below -->
<xsl:template match="@*|node()">
<xsl:copy>
<xsl:apply-templates select="@*|node()"/>
</xsl:copy>
</xsl:template>
<!-- Sort based on id node -->
<xsl:template match="include">
<xsl:copy>
<xsl:apply-templates select="data">
<xsl:sort select="id"/>
</xsl:apply-templates>
</xsl:copy>
</xsl:template>
<!-- Recalculate bsalary node -->
<xsl:template match="/include/data/bsalary">
<xsl:choose>
<xsl:when test="../type[text()]='Intern' and ../month[text()]>=3">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 1.2567"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<xsl:when test="../type[text()]='Staff' and ../month[text()]>=3">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 1.4533"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<xsl:when test="../type[text()]='Employee' and ../month[text()]>=3">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 1.6969"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<!-- Copy all nodes not affected by the rules above -->
<xsl:otherwise>
<xsl:copy>
<xsl:apply-templates select="@*|node()"/>
</xsl:copy>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<!-- Recalculate asalary node -->
<xsl:template match="/include/data/asalary">
<xsl:choose>
<xsl:when test="../type[text()]='Intern' and ../month[text()]>=6">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 1.8828"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<xsl:when test="../type[text()]='Staff' and ../month[text()]>=6">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 2.3549"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<xsl:when test="../type[text()]='Employee' and ../month[text()]>=6">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 2.6467"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<!-- Copy all nodes not affected by the rules above -->
<xsl:otherwise>
<xsl:copy>
<xsl:apply-templates select="@*|node()"/>
</xsl:copy>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<!-- Recalculate msalary node -->
<xsl:template match="/include/data/msalary">
<xsl:choose>
<xsl:when test="../type[text()]='Intern' and ../month[text()]>=12">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 2.4545"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<xsl:when test="../type[text()]='Staff' and ../month[text()]>=12">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 3.0611"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<xsl:when test="../type[text()]='Employee' and ../month[text()]>=12">
<xsl:copy>
<xsl:apply-templates select="@*"/>
<xsl:value-of select="substring(text(), 1, string-length(text()) - 1) * 3.8432"/>
<xsl:text>$</xsl:text>
</xsl:copy>
</xsl:when>
<!-- Copy all nodes not affected by the rules above -->
<xsl:otherwise>
<xsl:copy>
<xsl:apply-templates select="@*|node()"/>
</xsl:copy>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
</xsl:stylesheet>
