Musk may have paid little or no federal income taxes since at least 2014—despite his ballooning fortune—so the one-time payment of $8.3 billion (or even $11 billion) in essence covers multiple years. According to ProPublica’s analysis of IRS records, Musk paid no federal income taxes in 2018. Between 2014 and 2018 his wealth grew by $13.9 billion, yet he paid just $455 million in federal income taxes, a rate of only 3.27%.
https://americansfortaxfairness.org/musks-11-billion-tax-bill-big-news-just-10-wealth-increase-far-year/