code>) to use up to the last year of the source data.</p></dd>


<dt>exclude_years</dt>
<dd><p>Numeric vector of years to exclude from analysis. Leave blank or set to <code>NULL</code> to include all years.</p></dd>


<dt>months</dt>
<dd><p>Numeric vector of months to include in analysis. For example, <code>3</code> for March, <code>6:8</code> for Jun-Aug or 
<code>c(10:12,1)</code> for first four months (Oct-Jan) when <code>water_year_start = 10</code> (Oct). Default summarizes all 
months (<code>1:12</cod