Converts Excel dates encoded as serial numbers to date class.
Details
Defaults to the modern Excel date encoding system. Excel for Mac 2008 and earlier Mac versions of Excel use a different date system. If the date 2016-01-01 is represented by 42370, it's the modern system. If it's 40908, it's the old system.
See also
Other floor:
dtt_date(),
dtt_date_time(),
dtt_excel_to_time(),
dtt_floor(),
dtt_floored(),
dtt_set_time()
