If I run any report in 2.7.3 and then download it in excel format, the spreadsheet values are all represented with printed hyperlink code.

i.e. Course field is populated with:
<a href=http://moodle.site.net/course/view.php?id=123">coursename</a>

User full name is populated with:
<a href="http://moodle.site.net/user/view.php?id=1&course=123">some body</a>