You have also used an Australian index and a US dollar gold...

You have also used an Australian index and a US dollar gold price, if you had used the Aussie gold price chart, it again would look a lot different.

In the timeframe of the chart you posted, US dollar gold
has gone up nearly 500%, but in Aussie dollars the gold price has only gone up around 200%.

Charts are like statistics, you can make them paint different pictures, depending upon what you want to make out of them.

cheers grant