He hasn’t done that with rockets. He wants to eventually, but he hasn’t yet. Let’s not let hype cloud facts.
Comparisons with non-domestic rockets are complicated by state subsidies and differentials in labor costs. But the Falcon 9 is approaching the 10X mark even before reusability has been priced in. Both the Falcon Heavy (in a few months) and the (eventual) reusable pricing should overshoot the 10X mark substantially.
[1] I went to rocketbuilder.com and both LEO configurations I tried were around $8,000/kg (and I didn't count the 20% deduction for "ULA added value" since the numbers there are debatable)
The GAO cites $164M/launch as the price for the cheapest Delta V[3] (is there some kind of threshold at $165M?), which when the Falcon 9 was introduced could put 8,500kg to LEO[4], or $19,294/kg. (It has since been uprated and gotten slightly cheaper).
Must've screwed up my calculations earlier, because those aren't tallying. Anyhow, as you can see, SpaceX is already around 7x cheaper compared to where ULA was, and should cross the 10x threshold shortly. Nice to see ULA responding to competitive pressure, however!
1: https://web.archive.org/web/20160324172526/http://www.ulalau...
2: https://en.wikipedia.org/wiki/Atlas_V