title: In a currency exchange rate what is the maximum number of decimal places used?
body: <p>I need to store <strong>currency exchange rate</strong> data in the SQL 2008 database.
  I would like to keep rate as a <code>decimal</code> data type in the database.</p>
  
  <p>One thing I am not sure about, is <strong>how many decimal places to give</strong> (<strong>e.g. decimal(18, ?)</strong>).</p>
  
  <p>Since, I will be using this service as a source: <a href="http://openexchangerates.org/latest.json">http://openexchangerates.org/latest.json</a>. There, it seems that the highest number of decimal places used is '<strong>6</strong>'.</p>
  
  <p>Is that the right number, or there possibly can be rates with more than <strong>6</strong> decimal places?</p>