> example from today until 1 year - any MinFlowDate which falls within that 
> range will be summed

assuming you have dd/mm/yyyy then:

<xsl:value-of select="sum(Trade/Step
   [concat(substring(MinFlowDate,7),substring(MinFlowDate,4,2),substring(MinFlowDate,1,2))&gt;= 20041129]
   [concat(substring(MinFlowDate,7),substring(MinFlowDate,4,2),substring(MinFlowDate,1,2))&lt;  20051129]
   /StepCharge_TTBlack)"/>

does the total, the same without the Trade/ at the beginning would give
the sum for each trade separately (if the Trade elements were the
current node in that case)

David

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