A report has the Total subtotal enabled and it shows as below in Strategy Web 9.4.1 and above:

After exporting to Excel, the format isn't retained and it shows incorrectly:

In Strategy Developer, "Do not merge or duplicate headers when exporting to Excel/Word" is selected under Project configuration > Project definition > Export Settings.

Unselect the setting "Do not merge or duplicate headers when exporting to Excel/Word".
Strategy recommends that you only select this check box if instructed to do so by Strategy Technical Support. By default, this check box is cleared.