The previous patch (fixed for MySQL 4.0.x)

with added support for Tax Subtotals.
(the original version doesn't display properly order totals as it doesn't take into account Taxes)

after installing the original contribution, please replace stats_detailed_monthly_sales.php in /catalog/admin/

add the following line to
/catalog/admin/includes/languages/english/stats_detailed_monthly_sales.php

define('TABLE_HEADING_TOTAL_TAX','Tax');



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