XSLT syntax for if then else or when-otherwise - xslt

Question

Very new to xslt (still). I think I need to use a 'When-Otherwise' to do the following (correct me if I'm wrong), so looking for some guidance on correct syntax for the following logic:
When 'Contribution_Amount' is <=0, then ignore the row and do not output.
Otherwise return 'Contribution_Amount'.
Or I could also use opposite if that's easier/better
When 'Contribution_Amount' is >0, then 'Contribution_Amount'
Otherwise do not produce output
Here is the xsl. Any suggestions or help would be greatly appreciated. Thanks in advance!
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:out="http://www.workday.com/integration/output"
xmlns:etv="urn:com.workday/etv" exclude-result-prefixes="xs" version="2.0"
xmlns:xtt="urn:com.workday/xtt"
xmlns:wd="urn:com.workday.report/Pay_Calculation_Results_-__Deduction_Register">
<xsl:template match="wd:Report_Data">
<File xtt:separator="
">
<Header xtt:separator="|">
<Record_Type>FH</Record_Type>
<Administractor_Code>FTB</Administractor_Code>
<Employer_Code>555</Employer_Code>
<Flag></Flag>
<Submitted_Date><xsl:value-of select="format-date(current-date(),'[M01][D01][Y0001]')"/></Submitted_Date>
<Submitted_Time><xsl:value-of select="format-time(current-time(),'[H01][m01][s01]')"/></Submitted_Time>
<File_Version>2.0</File_Version>
</Header>
<xsl:for-each-group select="wd:Report_Entry" group-by="wd:Worker/wd:SSN">
<xsl:for-each-group select="current-group()" group-by="wd:Deduction_Description">
<CT xtt:separator="|">
<Record_Type>CT</Record_Type>
<Participant_File_Import_Id><xsl:value-of select="wd:Worker/wd:SSN"/></Participant_File_Import_Id>
<Plan_Name>HSA</Plan_Name>
<contribution_date><xsl:value-of select="format-date(wd:Payment_Date,'[M01][D01][Y0001]')"/></contribution_date>
<Contribution_desc><xsl:value-of select="wd:Deduction_Description"/></Contribution_desc>
<contribution_Amount><xsl:value-of select="format-number(sum(current-group()//wd:Current_Period_Result),'#0.00')"/></contribution_Amount>
<amount_type>Actual</amount_type>
</CT>
</xsl:for-each-group>
</xsl:for-each-group>
<Footer xtt:separator="|">
<xsl:variable name="Total_Count" select="count(wd:Report_Entry)"/>
<Record_Type>FF</Record_Type>
<Record_Count><xsl:value-of select="$Total_Count + 2"/></Record_Count>
<Administrator_Total>FTB</Administrator_Total>
<Employer_Code>555</Employer_Code>
<Submitted_Date><xsl:value-of select="format-date(current-date(),'[M01][D01][Y0001]')"/></Submitted_Date>
<Submitted_Time><xsl:value-of select="format-time(current-time(),'[H01][m01][s01]')"/></Submitted_Time>
</Footer>
</File>
</xsl:template>
</xsl:stylesheet>
Here is the xml input. I labeled it 1.0 because that's what our original developer created it as. I'm not versed enough to really know the difference or when to switch it over, apologies.
<?xml version='1.0' encoding='UTF-8'?>
<wd:Report_Data xmlns:wd="urn:com.workday.report/Pay_Calculation_Results_-__Deduction_Register">
<wd:Report_Entry>
<wd:Payroll_Result wd:Descriptor="Daffy Duck | Daffy Duck (12345): 03/08/2020 (Regular) - Complete">
<wd:ID wd:type="WID">1</wd:ID>
</wd:Payroll_Result>
<wd:Worker wd:Descriptor="Daffy Duck | Daffy Duck (12345)">
<wd:ID wd:type="WID">6</wd:ID>
<wd:ID wd:type="Employee_ID">12345</wd:ID>
</wd:Worker>
<wd:Worker>
<wd:SSN>123456789</wd:SSN>
</wd:Worker>
<wd:Employee_ID>12345</wd:Employee_ID>
<wd:Company wd:Descriptor="ACME Corp">
<wd:ID wd:type="WID">2</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">ACME</wd:ID>
<wd:ID wd:type="Company_Reference_ID">ACME</wd:ID>
</wd:Company>
<wd:Organizations wd:Descriptor="Cost Center: Management Team 90">
<wd:ID wd:type="WID">3</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">10090</wd:ID>
<wd:ID wd:type="Cost_Center_Reference_ID">10090</wd:ID>
</wd:Organizations>
<wd:Organizations wd:Descriptor="Location: Location 1">
<wd:ID wd:type="WID">4</wd:ID>
<wd:ID wd:type="Location_ID">LOC01</wd:ID>
</wd:Organizations>
<wd:Period wd:Descriptor="02/24/2020 - 03/08/2020 (Bi-weekly (Mon-Sun))">
<wd:ID wd:type="WID">5</wd:ID>
<wd:ID wd:type="Period_ID">19</wd:ID>
</wd:Period>
<wd:Deduction>HSA Employer Contribution</wd:Deduction>
<wd:Deduction_Description>Employer Contribution</wd:Deduction_Description>
<wd:Payment_Date>2020-03-13-07:00</wd:Payment_Date>
<wd:Deduction_Code>HSA ER CON</wd:Deduction_Code>
<wd:Current_Period_Result>41.66</wd:Current_Period_Result>
</wd:Report_Entry>
<wd:Report_Entry>
<wd:Payroll_Result wd:Descriptor="Daffy Duck | Daffy Duck (12345): 03/08/2020 (Regular) - Complete">
<wd:ID wd:type="WID">1</wd:ID>
</wd:Payroll_Result>
<wd:Worker wd:Descriptor="Daffy Duck | Daffy Duck (12345)">
<wd:ID wd:type="WID">6</wd:ID>
<wd:ID wd:type="Employee_ID">12345</wd:ID>
</wd:Worker>
<wd:Worker>
<wd:SSN>123456789</wd:SSN>
</wd:Worker>
<wd:Employee_ID>12345</wd:Employee_ID>
<wd:Company wd:Descriptor="ACME Corp">
<wd:ID wd:type="WID">2</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">ACME</wd:ID>
<wd:ID wd:type="Company_Reference_ID">ACME</wd:ID>
</wd:Company>
<wd:Organizations wd:Descriptor="Cost Center: Management Team 90">
<wd:ID wd:type="WID">3</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">10090</wd:ID>
<wd:ID wd:type="Cost_Center_Reference_ID">10090</wd:ID>
</wd:Organizations>
<wd:Organizations wd:Descriptor="Location: Location 1">
<wd:ID wd:type="WID">4</wd:ID>
<wd:ID wd:type="Location_ID">LOC01</wd:ID>
</wd:Organizations>
<wd:Period wd:Descriptor="02/24/2020 - 03/08/2020 (Bi-weekly (Mon-Sun))">
<wd:ID wd:type="WID">5</wd:ID>
<wd:ID wd:type="Period_ID">19</wd:ID>
</wd:Period>
<wd:Deduction>HSA - Contribution</wd:Deduction>
<wd:Deduction_Description>Payroll Deduction</wd:Deduction_Description>
<wd:Payment_Date>2020-03-13-07:00</wd:Payment_Date>
<wd:Deduction_Code>HSA</wd:Deduction_Code>
<wd:Current_Period_Result>254.17</wd:Current_Period_Result>
</wd:Report_Entry>
<wd:Report_Entry>
<wd:Payroll_Result wd:Descriptor="Daffy Duck | Daffy Duck (12345): 03/08/2020 (Regular) - Complete">
<wd:ID wd:type="WID">1</wd:ID>
</wd:Payroll_Result>
<wd:Worker wd:Descriptor="Daffy Duck | Daffy Duck (12345)">
<wd:ID wd:type="WID">6</wd:ID>
<wd:ID wd:type="Employee_ID">12345</wd:ID>
</wd:Worker>
<wd:Worker>
<wd:SSN>123456789</wd:SSN>
</wd:Worker>
<wd:Employee_ID>12345</wd:Employee_ID>
<wd:Company wd:Descriptor="ACME Corp">
<wd:ID wd:type="WID">2</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">ACME</wd:ID>
<wd:ID wd:type="Company_Reference_ID">ACME</wd:ID>
</wd:Company>
<wd:Organizations wd:Descriptor="Cost Center: Management Team 90">
<wd:ID wd:type="WID">3</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">10090</wd:ID>
<wd:ID wd:type="Cost_Center_Reference_ID">10090</wd:ID>
</wd:Organizations>
<wd:Organizations wd:Descriptor="Location: Location 1">
<wd:ID wd:type="WID">4</wd:ID>
<wd:ID wd:type="Location_ID">LOC01</wd:ID>
</wd:Organizations>
<wd:Period wd:Descriptor="02/24/2020 - 03/08/2020 (Bi-weekly (Mon-Sun))">
<wd:ID wd:type="WID">5</wd:ID>
<wd:ID wd:type="Period_ID">19</wd:ID>
</wd:Period>
<wd:Deduction>HSA - Contribution</wd:Deduction>
<wd:Deduction_Description>Payroll Deduction</wd:Deduction_Description>
<wd:Payment_Date>2020-03-13-07:00</wd:Payment_Date>
<wd:Deduction_Code>HSA</wd:Deduction_Code>
<wd:Current_Period_Result>-250</wd:Current_Period_Result>
</wd:Report_Entry>
<wd:Report_Entry>
<wd:Payroll_Result wd:Descriptor="Daffy Duck | Daffy Duck (12345): 03/08/2020 (Regular) - Complete">
<wd:ID wd:type="WID">1</wd:ID>
</wd:Payroll_Result>
<wd:Worker wd:Descriptor="Daffy Duck | Daffy Duck (12345)">
<wd:ID wd:type="WID">6</wd:ID>
<wd:ID wd:type="Employee_ID">12345</wd:ID>
</wd:Worker>
<wd:Worker>
<wd:SSN>123456789</wd:SSN>
</wd:Worker>
<wd:Employee_ID>12345</wd:Employee_ID>
<wd:Company wd:Descriptor="ACME Corp">
<wd:ID wd:type="WID">2</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">ACME</wd:ID>
<wd:ID wd:type="Company_Reference_ID">ACME</wd:ID>
</wd:Company>
<wd:Organizations wd:Descriptor="Cost Center: Management Team 90">
<wd:ID wd:type="WID">3</wd:ID>
<wd:ID wd:type="Organization_Reference_ID">10090</wd:ID>
<wd:ID wd:type="Cost_Center_Reference_ID">10090</wd:ID>
</wd:Organizations>
<wd:Organizations wd:Descriptor="Location: Location 1">
<wd:ID wd:type="WID">4</wd:ID>
<wd:ID wd:type="Location_ID">LOC01</wd:ID>
</wd:Organizations>
<wd:Period wd:Descriptor="02/24/2020 - 03/08/2020 (Bi-weekly (Mon-Sun))">
<wd:ID wd:type="WID">5</wd:ID>
<wd:ID wd:type="Period_ID">19</wd:ID>
</wd:Period>
<wd:Deduction>HSA - Contribution</wd:Deduction>
<wd:Deduction_Description>Payroll Deduction</wd:Deduction_Description>
<wd:Payment_Date>2020-03-13-07:00</wd:Payment_Date>
<wd:Deduction_Code>HSA</wd:Deduction_Code>
<wd:Current_Period_Result>250</wd:Current_Period_Result>
</wd:Report_Entry>
</wd:Report_Data>

Answer 1

I would have streamlined this to:
<xsl:variable name="amt" select="sum(current-group()//wd:Current_Period_Result)" />
<xsl:if test="$amt">
<contribution_Amount>
<xsl:value-of select="format-number($amt, '0.00')"/>
</contribution_Amount>
</xsl:if>
(Should be a comment, but it's too much code).

Answer 2

I think I got it guys! I went with this:
<xsl:if test="format-number(sum(current-group()//wd:Current_Period_Result),'#0.00') > '0.00'">
<contribution_Amount><xsl:value-of select="format-number(sum(current-group()//wd:Current_Period_Result),'#0.00')"/></contribution_Amount>
</xsl:if>