As usual, Tesla Inc (NASDAQ:TSLA) is garnering plenty of headlines. Most recently, it's because the beloved and controversial stock entered the S&P 500, but there's more to the story.

What Happened: It seems like nary a day goes by that a new electric vehicle doesn't pop or a special purpose acquisition company (SPAC) focusing on the EV industry doesn't appear. However, Tesla is the barometer by which all EV rookies are measured.

That works in favor of the exchange-traded funds with hefty allocations to Elon Musk's company, including the ARK Autonomous Technology & Robotics ETF (CBOE: ARKQ).

ARKQ is one of three ARK Investment Management ETFs featuring Tesla as the largest component, but ARKQ's 11.71% allocation to the stock exceeds that of its stablemates.

Why It's Important: ARKQ's significant Tesla exposure helped the fund more than double this year, but the auto manufacturer's proficiency in $/charging rate, or miles of range added per minute of charging, could be an ongoing catalyst for both the shares and the ARK ETF.

“Our research aims to forecast the price and performance of EVs during the next five to ten years. To date, we have used Wright’s Law to forecast battery cost declines,” according to ARK Research. “Because the battery is its largest cost component, typically 20%, we can forecast the long-term decline in EV sticker prices.”

Typically, $/kilowatt-hour (kWh) has been used as the primary gauge of battery success in the EV market, but milestones are often harder to quantify.

“Forecasting other EV specifications is less straightforward, particularly metrics like range, efficiency (range/kWh), time to accelerate from 0-60mph, and battery pack size,” notes ARK. “Complicating the analysis further are battery cell chemistries with different $/kWh costs and performance tradeoffs.”

What's Next: Enhancing the long-term allure of ARKQ, of which there's plenty beyond Tesla, is the automobile maker's ability to keep competition at bay when it comes to $/charging rate. In fact, many new EVs can't match the $/charging rate the Model 3 had two years ago.

“Incorporating all specifications and equilibrating the comparison is a metric called 'charging rate', or miles of range added per minute,” according to ARK. “As measured by $/charging rate, most EVs today have yet to match the Tesla Model 3 circa 2018. Our analysis indicates that none come close to the 2020 Model 3.”