Task: Question Answering
Input (English): Passage: After the August 15, 1971 Nixon shock, the price began to greatly increase, and between 1968 and 2000 the price of gold ranged widely, from a high of $850 per troy ounce ($27.33/g) on January 21, 1980, to a low of $252.90 per troy ounce ($8.13/g) on June 21, 1999 (London Gold Fixing). Prices increased rapidly from 2001, but the 1980 high was not exceeded until January 3, 2008, when a new maximum of $865.35 per troy weight was set. Another record price was set on March 17, 2008, at $1023.50 per troy ounce ($32.91/g). 
Question: How many more dollars was the price of gold on January 21, 1980 compared to June 21, 1999? 
Answer type: Number 
Output (English): 597.10.