The National Stock Exchange (NSX) has released the August numbers for exchange traded funds (ETFs) and exchange traded notes (ETNs).

Together, assets reached $596.5 billion, a 15% increase over $518.9 billion ayear ago.

Net cash inflows for the month of August totaled $11.4 billion, with notional trading volume at $1.7 trillion, a representation of 31% of all U.S. equity trading volume.

The top three ETFs by net cash inflow were

1) SPDR Index 500 (SPY): $3,586 million; the fund was up 1.5% for the month

2) iShares MSCI EAFE (EFA): $432 million; the fund was up 2.1% for the month

3) iShares MSCI Emerging Markets (EEM): $562 million; the fund was down 5.7% for the month