The ETF market is on track to swell to $7.6 trillion by the end of 2020 from just under $5 trillion currently, it found.
In order to keep the cash flowing in, ETF fees, which averaged just 27 basis points last year, will have to keep falling. Being a low-cost provider is a "prerequisite to survival," the EY survey found.
A report by financial services firm bfinance earlier this year showed that active fund management fees are also falling, with the average fee quoted by global equity managers now around 57 basis points compared with 62 basis points in 2015.
But that's around double the average that passive fund fee investors are paying for what is, on average, a worse performance.
This article was provided by Reuters.