He commented: "This is my eighth and final Royal Ascot as Chief Executive at Ascot, a position which I consider it a privilege to hold. It is a great honour to be part of today's Royal Procession."
Barnett joined Ascot in 2007, having previously been Managing Director of Aintree Racecourse. He retires from his position at Ascot later this year.
He arrived the year after the opening of the new Grandstand.
"There were one or two dramas at that time so we had to deal with a few media problems, most of which were resolved quite quickly. It has just taken time but people have begun to love this stand now.
"We have made the Grandstand more user friendly and instituted changes to appeal to the customer. The whole team at Ascot has worked very hard on that and it is an ongoing process.
"What we have done over the last few years is to reduce our capacities to give more comfort for everyone coming here. We want people to really enjoy the experience.
"Her Majesty The Queen was the first reigning monarch to win the Gold Cup with Estimate since the race was founded in 1807. The 2013 Gold Cup was simply an amazing race and wonderful for us all to be here to see.
"This year's Gold Cup was extraordinary too; after two and a half miles to have three horses battling it out and less than half a length covering them all at the finish. Estimate ran a most brilliant race in second to finish so close to last year's St Leger winner, Leading Light.
"Yeats winning his fourth Gold Cup (in 2009) was an emotional moment and he was a magnificent horse. Black Caviar just getting home in the 2012 Diamond Jubilee Stakes was another tremendous moment and the brilliant Frankel ran and won at Ascot five times and was incredibly impressive in the Queen Anne Stakes.
"We are terribly fortunate at Ascot - it is the best racing in the world. We have had unbelievable sprinters, particularly from Australia and starting with Choisir, as well as horses from Hong Kong, New Zealand, Singapore, all over Europe and now America.
"We start planning a long way out for the following year's Royal Ascot and it is constantly evolving. We are trying to give people something a bit different each year."