title: SQL Server DATEDIFF round up the YEAR difference. How to round it down?
body: <p>I have a problem that I tried googling but most questions are about rounding down hours or minutes.</p>
  <p>I'm checking birthday dates for users and I have two dates that are 99.3 years apart. That means that the user is 99 years old but this piece of code:</p>
  <pre><code>DATEDIFF(YEAR, r.BirthDate, ISNULL(@Date,GETDATE()))
  </code></pre>
  <p>returns a value of 100. Is there a way to round the value down?</p>