Incorrect Response

I am trying to get the correct currency from Euro to US Dollar.  The response should pick up as 1.318 but instead when I run the script, the value picks up as -1.  Below is the code that I am executing:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:web="http://www.webserviceX.NET/">
   <soapenv:Header/>
   <soapenv:Body>
      <web:ConversionRate>
         <web:FromCurrency>EUR</web:FromCurrency>
         <web:ToCurrency>USD</web:ToCurrency>
      </web:ConversionRate>
   </soapenv:Body>
</soapenv:Envelope>

This is the result I get when I run the script:

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
   <soap:Body>
      <ConversionRateResponse xmlns="http://www.webserviceX.NET/">
         <ConversionRateResult>-1</ConversionRateResult>
      </ConversionRateResponse>
   </soap:Body>
</soap:Envelope>

Please explain why I am getting a value of -1 in "ConversionRateResponse".

Thanks,

Kevin