.number{
text-align: right;
}
.ruiColumnWidth{
width: 15%;
}
.ruiMonthEven{
background: ⌗F5F5F5;
}
.ruiMonthOdd{
}
<apex:pageBlockTable value="{!ruiWrappers}" var="wrapper" cellpadding="5">
<apex:column headerValue="Amount" styleClass="number ruiColumnWidth {!IF(wrapper.monthType == 'Even', 'ruiMonthEven', 'ruiMonthOdd')}" headerClass="number">
<apex:outputField value="{!wrapper.rui.RuiPipeline__c}"/>
</apex:column>
<apex:column headerValue="Probability" styleClass="ruiColumnWidth {!IF(wrapper.monthType == 'Even', 'ruiMonthEven', 'ruiMonthOdd')}">
<apex:outputText value="{!wrapper.ruiProbability}"/>
</apex:column>
</apex:pageBlockTable>
.number{
text-align: right;
padding-right: 5px;
}
.ruiColumnWidth{
width: 15%;
}
.ruiMonthEven{
background: ⌗F5F5F5;
}
.ruiMonthOdd{
}
<apex:pageBlockTable value="{!ruiWrappers}" var="wrapper">
<apex:column headerValue="Amount" styleClass="number ruiColumnWidth {!IF(wrapper.monthType == 'Even', 'ruiMonthEven', 'ruiMonthOdd')}" headerClass="number">
<apex:outputField value="{!wrapper.rui.RuiPipeline__c}"/>
</apex:column>
<apex:column headerValue="Probability" styleClass="ruiColumnWidth {!IF(wrapper.monthType == 'Even', 'ruiMonthEven', 'ruiMonthOdd')}">
<apex:outputText value="{!wrapper.ruiProbability}"/>
</apex:column>
</apex:pageBlockTable>