ETFs were seen as an insignificant niche before the financial crisis that provides a low-cost way of investing in the asset basket via index tracking. However, many investors failed to avoid damaged losses in the course of the crisis by most conventional active managers, and so we're looking at less volatile ETF strategies. Over the past decade, these financial instruments collected more than $3.5 tons of new cash.

The penetration of ETF index-tracking into financial markets "has a great deal to go," stated Inigo Fraser-Jenkins. Senior analyst of the brokerage Bernstein. The growth of ETFs helped BlackRock and Vanguard, the indexing fund pioneer, to develop into the two largest and most influential players in the asset management industry.

The iShares ETF subsidiary of BlackRock has so far raised at least $125 billion in new money this year, raising assets beyond $2 million in October. Rapid iShare growth has brought the total assets of BlackRock to a record of $7tn.

ETF inflows have helped Vanguard, based in Pennsylvania, retain for seven consecutive years the title of the world's rapidly growing fund manager. This year Vanguard's ETF arm has raised its total assets to $5.9 million, at least $88 billion in new cash.

The opponents waged an aggressive price war against duties in smaller competitors, including State Street, Charles Schwab, DWS, Lyxor, UBS and Amundi. The fight has created relentless pressures on profit margins throughout the fund industry and has forced further strengthening.

Recent research from Goldman Sachs found that the volatility of the underlying stocks is influenced by ETF trade. Some scientists also believe that ETF flows are distorting the critical price discovery function of the US stock market, which could lead to capital misallocation and eventual harm to economic growth.

Regulators know that the vast asset acquisition programs that central banks have introduced after the financial crisis has contributed to driving American inventories up to all times and creating potential hazardous bubbles on bond markets.

There is doubt in the minds of many officials as to whether orderly trading could be interference with the large-scale market correction of ETFs, resulting in a damaging downward spiral and greater losses for investors.