The four ETFs track a revised S&P Target Risk Index Series benchmark that will rebalance on an annual basis. All ticker symbols will remain the same and net expense ratios for iShares Core Allocation ETFs will range from 23 to 25 basis points, according to a statement issued by BlackRock. The four core additions have a combined $1.62 billion in assets under management.

When iShares rolled out its 10-ETF suite of core funds in October 2012, the intent appeared to be to give retail investors some low-cost options from the iShares stable. However, there has been wide institutional adoption of the funds, as highlighted by asset growth for some of the original core ETFs. For example, the iShares Core MSCI Emerging Markets ETF (NYSEArca: IEMG)now has over $6.1 billion in assets while the iShares Core MSCI EAFE ETF (NYSEArca: IEFA) is now a $3.4 billion fund. [Core ETFs Gain Institutional Support]

With the addition of AOK, AOM, AOA and AOR to its core lineup, iShares now has 24 ETFs in that group.

Prior to Monday, the most recent addition to the iShares core suite occurred in June 2014 when the firm added 10 ETFs, including four new funds.

iShares Core Conservative Allocation ETF

ETF Trends editorial team contributed to this post. Tom Lydon’s clients own shares of EEM, EFA and IVV.