Getting a Value from XML File

So I've been trying to figure out XML file formats as I am very new to them. I feel I am getting close but not quite there. I have uploaded a version of the XML as a .txt file with only the pertinent info in. Below is my code:

Params = xmlread('Test1text.xml').getElementsByTagName('ParameterValue');

for k = 0:Params.getLength-1
    thisParam = Params.item(k);
    thisAttr = thisParam.getAttribute('parameter');
    if thisAttr == 'pa9'
        ParamChildren = thisParam.getChildNodes;
        thisData = ParamChildren.item(0);
        Ex = thisData
        disp('Ex');
        disp(Ex);
    end
end

Unfortunatley this outputs:

" Ex

[#text:

] "

From the attatched xml, I would like it to output something like:

Ex

181

Therefore, I will have assigned the value of the Data node ( that is the child of the ParamererValue node with attribute parameter = "pa9" ) to var Ex

Really appreciate any and all help/advice.