How much is a 1991 Proof Krugerrand worth?

As the value of bullion Krugerrand coins is very much tied to the price of gold it is difficult to determine the price of a 1991 Proof Krugerrand. However, a good estimate for a 1991 Proof Krugerrand would be about 110% of the gold price.
On the 29 June 2016 a 1991 Proof Krugerrand set 1.85 Oz was sold on ebay for US$ 2950 which would be around 119% of the gold price.