Defining the strength of a transition graph by counting?

Hello everybody,

currently I want to generate a transition graph of people transitioning from one hotel into another year by year. This generation was no problem, but when it comes to the strength and the activation of the "edge labels" I don't know what to do. 

What I want to achieve is, that the amount of people changed is displayed as the strength or the "edge label". I tried different solutions with the aggregate Operator but if I aggregate for example the numer of hotels the "edge label" is for each edge the same...

I hope someone can help me there.

<?xml version="1.0" encoding="UTF-8"?><process version="7.4.000">
  <context>
    <input/>
    <output/>
    <macros/>
  </context>
  <operator activated="true" class="process" compatibility="7.4.000" expanded="true" name="Process">
    <process expanded="true">
      <operator activated="true" class="retrieve" compatibility="7.4.000" expanded="true" height="68" name="Retrieve Flatfile_Kundenwanderung_20170331 V04 roh" width="90" x="45" y="34">
        <parameter key="repository_entry" value="//Local Repository/Flatfile_Kundenwanderung_20170331 V04 roh"/>
      </operator>
      <operator activated="true" class="select_attributes" compatibility="7.4.000" expanded="true" height="82" name="Select Attributes" width="90" x="246" y="34">
        <parameter key="attribute_filter_type" value="subset"/>
        <parameter key="attributes" value="Action_2013|Action_2014|Action_2015|Action_2016|CRMPrivatkundeID|PLZ|Land|Kundensegment|Kundengruppe|Haushaltstyp|Geschlecht|Geburtsjahr|DauerKundenbeziehung|Bundesland|Buchungsmuster|Bevorzugtebuchungsart|Alter heute Klasse|Alter heute"/>
      </operator>
      <operator activated="true" class="aggregate" compatibility="7.4.000" expanded="true" height="82" name="Aggregate" width="90" x="313" y="238">
        <list key="aggregation_attributes">
          <parameter key="Action_2013" value="count"/>
        </list>
        <parameter key="group_by_attributes" value="Action_2013"/>
      </operator>
      <operator activated="true" class="join" compatibility="7.4.000" expanded="true" height="82" name="Join" width="90" x="514" y="238">
        <parameter key="join_type" value="right"/>
        <parameter key="use_id_attribute_as_key" value="false"/>
        <list key="key_attributes">
          <parameter key="Action_2013" value="Action_2013"/>
        </list>
      </operator>
      <operator activated="true" class="transition_graph" compatibility="7.4.000" expanded="true" height="82" name="Transition Graph" width="90" x="447" y="34">
        <parameter key="source_attribute" value="Action_2013"/>
        <parameter key="target_attribute" value="Action_2014"/>
        <parameter key="strength_attribute" value="count(Action_2013)"/>
      </operator>
      <connect from_op="Retrieve Flatfile_Kundenwanderung_20170331 V04 roh" from_port="output" to_op="Select Attributes" to_port="example set input"/>
      <connect from_op="Select Attributes" from_port="example set output" to_op="Aggregate" to_port="example set input"/>
      <connect from_op="Aggregate" from_port="example set output" to_op="Join" to_port="left"/>
      <connect from_op="Aggregate" from_port="original" to_op="Join" to_port="right"/>
      <connect from_op="Join" from_port="join" to_op="Transition Graph" to_port="example set"/>
      <connect from_op="Transition Graph" from_port="example set" to_port="result 2"/>
      <connect from_op="Transition Graph" from_port="transition graph" to_port="result 1"/>
      <portSpacing port="source_input 1" spacing="0"/>
      <portSpacing port="sink_result 1" spacing="0"/>
      <portSpacing port="sink_result 2" spacing="0"/>
      <portSpacing port="sink_result 3" spacing="0"/>
    </process>
  </operator>
</process>