cal_date_time</a> <span class="special">&amp;</span> t<span class="special">,</span> <span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">gregorian</span><span class="special">::</span><span class="identifier">years</span> <span class="special">&amp;</span> y<span class="special">)</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.14.15.6.4.11.4"></a><h2>Description</h2>
<p>Subtracts a years obje