this wiorks if you have data for each day-not sure how to fill in the missing days without a calendar table.
I do not think that Excel will support an outer join as a datasource for (XI)
Make 7 formula
//MDforSunday
if datepart("w",table.datefield)=1 then totext(datepart("d",table.field),0)
//MDforMonday
if datepart("w",table.datefield)=2 then totext(datepart("d",table.field),0)
repeat for all 7 days
make group summary for each one as the max value and palce in the correct weekday box at the group header level