Very unscientific but here are photos of the Ascot crowd taken before the first races on Friday, Saturday and Sunday.
I have to say Friday was like a morgue with very little atmosphere. Saturday, as would be expected, was very busy. Sunday was a very decent crowd, certainly more than there would have been mid-week.
Friday
http://www.ors-racing.co.uk/Images/General/Friday.jpg
Saturday
http://www.ors-racing.co.uk/Images/General/Saturday.jpg
Sunday
http://www.ors-racing.co.uk/Images/General/Sunday.jpg