Publicists for both the award-winning musical acts were unable to provide the Otago Daily Times with numbers of tickets sold when asked this week.
Dunedin Venues Management Ltd, responding to an official information request by the Otago Daily Times, also refused to divulge details of the types of commercial deals used to secure their performances at Forsyth Barr Stadium.
DVML chief executive Darren Burden said each deal was undertaken on ''a confidential and commercial basis'', and details were withheld to allow DVML to conduct commercial activities ''without prejudice or disadvantage''.
He would only say all venue hire contracts differed, depending on the size of the event, logistics involved, and other variables, including the different risks faced by each promoter.
''The deal itself could be based on a flat venue fee, a percentage of ticket sales, inside charges on tickets, reimbursement of costs, or a mixture of a number of these things.''
It was hoped a crowd of 40,000 would pack the venue on April 24 to watch Aerosmith and support acts Wolfmother, the Dead Daisies, Head Like a Hole and Diva Demolition.
He also hoped for a sellout crowd of 35,000 for Paul Simon and support acts Rufus Wainwright and Aaradhna - with on-pitch seating reducing the capacity - on April 6, but would be ''pretty pleased'' with a crowd of 20,000 to 25,000.
The ODT understands fewer than 10,000 tickets have so far been sold for Paul Simon's concert, while about 15,000 have sold for Aerosmith's show.
However, DVML staff this week referred questions about ticket sales for the two concerts to publicists for the events, who would not give specifics.
Sandra Roberts, the publicist for McManus Entertainment, said tickets for Aerosmith's show were selling well, but declined to give a number.
Tickets for seated areas were selling ''very strongly'', and student tickets ''very well'', while restricted view tickets had just been released ''to give those on a budget an option'', she said.
Nancy Blackler, the publicist for Chugg Entertainment, was also unable to provide details of the number of tickets sold for Paul Simon's concert.