hahaha how convenient for you to use 1979 as your starting point. Firstly the gold price was $459 USD that year so it is well above a double return. What is ever so manipulative of you is to omit that Gold was less then half of 1979's price in 1978 where it was $208 USD. Or that it was $139 USD in 1975 or $38 USD per ounce in 1970!
Perhaps instead of manipulating data for your ego boast you should try use a generic 25 or 30 year graph and report back to us the results. Although I think that may be beyond your ego.