After expanding their exchange traded fund partnership less than a year ago, BlackRock (NYSE: BLK) and Fidelity Investments are already experiencing improved organic growth.

BlackRock revealed that growth of iShares ETFs on Fidelity’s broker platform, which provides commission-free trades on over 60 iShares ETFs, was 15% over 2013, compared to the 8% growth rate for the iShares business as a whole, reports Jackie Noblett for Financial Times. [ETFs Driving BlackRock Profit Growth]

“The expansion of the partnership earlier in the year probably contributed to that growth rate,” Ben Johnson, director of passive fund research at Morningstar, said in the article.

Meanwhile, Fidelity launched a line of 10 sector ETFs subadvised by BlackRock. The ETFs have an expense ratio of 0.12%, the lowest for sector ETFs on the market.

“We’re not in the beta space; that’s not who we are, and that’s not how we’re going to add value, but that’s what our clients are looking for, and it’s important for us to offer them what they want,” Greg Friedman, senior vice-president and head of product development and strategy at Fidelity SelectCo, said at the ETF Virtual Summit last week.