<p>I suppose it depends on how you define ‘extremely difficult’. Here’s the data. You can make that determination for yourself.</p>
<p><a href=“http://career.berkeley.edu/MedStats/19992003seniors.stm[/url]”>http://career.berkeley.edu/MedStats/19992003seniors.stm</a></p>
<p><a href=“http://career.berkeley.edu/MedStats/national.stm[/url]”>http://career.berkeley.edu/MedStats/national.stm</a></p>