customers.erb

<table>
    <% @c.each do |customer| %>  
        <tr>
              <td><%= customer.id %><td>
              <td><%= customer.email %></td>
              <td><a href="../customer/<%= customer.id %>">Subscriptions [<%= customer.subscriptions.total_count %>] </a></td>
        </tr>
    <% end %>
</table>