<apex:page controller="FiscalPivot_Class">
<apex:pageblock >
<apex:pageblocktable value="{!completeRowList}" var="row">
<apex:column >
<apex:outputtext >{!row.name}</apex:outputtext>
</apex:column>
<apex:repeat value="{!row.amountMap}" var="periodYear">
<apex:column>
<apex:facet name="header">{!periodYear}</apex:facet>
<apex:outputtext value="{0,number,⌗⌗⌗,⌗⌗⌗,⌗⌗0}" ><apex:param value="{!row.amountMap[periodYear]}"/></apex:outputtext>
</apex:column>
</apex:repeat>
<apex:column>
<apex:facet: name="header">Total</apex:facet:>
<apex:outputtext value="{0,number,⌗⌗⌗,⌗⌗⌗,⌗⌗0}" ><apex:param value="{!row.lineTotal}"/></apex:outputtext>
</apex:column>
</apex:pageblocktable>
</apex:pageblock>
</apex:page>
try setting the headerValue attribute on your apex:column like so: <apex:column headerValue="YOUR COLUMN HEADER" >
</apex:column>