S&P Dow Jones Indices announced yesterday that Tesla (TSLA) will be included in the popular S&P 500 index on December 21. Based on its current market capitalization, the world’s most valuable car maker will be one of the largest weight additions to the S&P 500 in the last decade. It will be among the S&P 500′s (SPY) ten most valuable companies.The index provider is seeking comments on whether Tesla should be included in one or two tranches, with the first tranche added one week earlier and the second tranche added effective on the rebalancing effective date.The stock is surging about 10% today. Tesla was expected to join the index in September when it posted a profit in four consecutive quarters, which is one of the requirements of joining the index. The stock had sold off a bit after S&P Dow Jones passed on it but it is still up about 400% this year.There is over $11.2 trillion indexed or benchmarked to the S&P 500 index, with indexed assets comprising approximately $4.6 trillion of this total. These index funds will be adding Tesla stock in the coming weeks. Currently, the Nasdaq 100 ETF (QQQ) is the only major index ETF that has Tesla among its holdings.The iShares U.S. Consumer Goods ETF (IYK), the SPDR S&P NYSE Technology ETF (XNTK), the ARK Autonomous Technology & Robotics ETF (ARKQ) and ARK Innovation ETF (ARKK) have high allocation to Tesla stock. Please watch the short video above to learn more.(Disclosure: I own shares of Tesla in my personal trading portfolio.)Want key ETF info delivered straight to your inbox?Zacks’ free Fund Newsletter will brief you on top news and analysis, as well as top-performing ETFs, each week. Get it free >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Tesla, Inc. (TSLA): Free Stock Analysis Report SPDR S&P 500 ETF (SPY): ETF Research Reports Invesco QQQ (QQQ): ETF Research Reports ARK Autonomous Technology & Robotics ETF (ARKQ): ETF Research Reports iShares U.S. Consumer Goods ETF (IYK): ETF Research Reports ARK Innovation ETF (ARKK): ETF Research Reports SPDR NYSE Technology ETF (XNTK): ETF Research Reports To read this article on Zacks.com click here. Zacks Investment Research Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report