9, iShares 20+ Year Treasury Bond ETF – TLT

Average Daily Volume: $1.04 billion

The iShares 20+ Year Treasury Bond ETF was a popular option for traders eyeing the Fed’s move on interest rates. TLT’s rank seems to be driven more by its share price than its volume: The fund traded 9 million shares per day on average in 2015.

8. SPDR Dow Jones Industrial Average ETF – DIA

Average Daily Volume: $1.19 billion

DIA, a fund that consistently trades heavily, may have seen higher volume in 2015 as the impact of weakening commodities, interest rate uncertainty and slowing emerging market economies weighed on investors. This mega-ETF saw an average of 6.2 million shares change hands each day of 2015.

7. Energy Select Sector SPDR Fund – XLE

Average Daily Volume: $1.29 billion

After dropping more than 20 percent in NAV across 2015, it makes sense that the XLE made the list. Plummeting oil prices combined with a glut in reserves played a primary role in the sector’s difficulties. The Energy Select Sector SPDR Fund traded a whopping 19 million shares a day.