The exchange-traded fund industry could reach $1 trillion in assets by 2019, predicts global investment manager BlackRock.

Exchange-traded product assets are set to hit the $500 billion milestone this year and surpass $1 trillion in under five years, says New York-listed BlackRock.

The prediction comes 15 years on from the launch of the first exchange-traded funds in Europe and swiftly follows BlackRock's launch of two new ETFs.

Exchange-traded funds reached $494 billion in assets at the end of last month. The original UK ETF, iShares Core FTSE 100 UCITS ETF, has become the largest UK equities ETF managing ÂŁ3.7 billion ($5.5 billion) in assets.

“ETFs are one of the success stories of twenty-first century investing in Europe,” said BlackRock's head of EMEA iShares, Rachel Lord.

“In just 15 years, this financial market has grown from scratch into an industry on the cusp of $500 billion, by providing levels of efficiency, transparency and value for money that have democratised investing for those across the continent.”

The industry now comprises 2,269 different exchange traded products in Europe, listed in 22 countries by 45 different providers.

BlackRock attributed its healthy growth forecast to a range of drivers, including a rise in optimism among European investors, as well as the global growth of passive investing.

“We see growth coming from investors who have previously deployed capital using products traded over-the-counter – bonds and futures especially – who are turning to ETFs for the first time because of the liquidity and low costs. There is a clear trajectory ahead, and we’re welcoming new European investors to ETFs every day,” Lord said.