Tesla Inc.’s market value topped $500 billion on Tuesday, setting the Silicon Valley electric-car maker on track to become the seventh largest company in the S&P 500 index once it is added to the benchmark in mid-December.

a car parked in a parking lotThe latest run comes ahead of the inclusion in the S&P 500, set for the start of trading on Dec. 21.

It took Tesla 111 days to go from a market valuation of $100 billion in mid-January to $200 billion by the end of June, then a short 13 days to get to $300 billion in mid-July.

Tesla tops $500 billion market value as shares hit all-time high

The $400 billion-mark, hit in August, took 27 days. From there it was a relatively slow 63 days to hit today’s $514 billion.

Underscoring the complexity of adding the heavyweight to the benchmark, S&P Dow Jones Indices took an unusual step, saying that it would consult with investors whether it would add Tesla in separate tranches or all at once.

The index announced its plan to add Tesla earlier this month.

Tesla’s addition to the broader, premier benchmark for U.S. equities, automatically will put the shares in the portfolios of countless index-tracking funds, cascading on to the many managed funds that would have to follow suit to balance their holdings. It will also provide even greater visibility and a measure of comfort with

Tesla shares for individual investors.Tesla’s stock run also mirrors the action in other electric-vehicle and electric vehicle-related stocks. American depositary receipts of Nio Inc. a Shanghai-based EV maker, have skyrocketed 1,200% this year.

Nikola Corp. shares have rallied 240% despite the fact that the electric-truck maker has no revenue and short sellers have raised many questions about its business model. Nikola earlier this month said it made “significant progress on key milestones.”

Tesla stock, which has hit more than 30 record closes this year, got yet another tailwind with the S&P addition news. It has gained 40% this month and nearly 550% this year, compared with gains of around 12% for the index.