<li><%= link_to 'List All Purchases', :action => 'list' %></li>
<li><%= link_to 'List All Purchases by Date', :action => 'filter', :type => 'date' %></li>
<li><%= link_to 'List All Purchases by a Customer', :action => 'filter', :type => 'customer' %></li>
+ <li><%= link_to 'Total Income by Date(s)', :action => 'income' %></li>
</ul>