I don't think that the performance is "divided", it's some sort other comparison.One can also link to them. Here are two alternative views of the same thing, relative performance of ARKK.
Here's the chart of ARKK:QQQ with the two prices divided
Here is ARKK (green) and QQQ (black) performance side by side
Both views have their advantages, for certain things.
Stockcharts always does total returns adjusted for dividends, which is a nice feature. You don't get that with many other chart sites.
It looks like ARKK was simply a leveraged QQQ, until late 2020, where it starts to diverge, and really breaks off in May 2021.
Overall looks like a higher volitility/riskier mix but not really superior. TTM is pretty poor performance.