Market Insights

Stocks just had their first losing month of the year, driving activity in index funds and volatility products.

ProShares UltraPro QQQ (TQQQ) jumped six places in TradeStation’s monthly list of busiest symbols. TQQQ’s No. 3 ranking was its highest in more than a year.

The fund is closely associated with other popular symbols in the Nasdaq-100 index like Apple (AAPL), Amazon.com (AMZN) and Tesla (TSLA).

May’s other big mover was the VelocityShares Daily 2x VIX short-term exchange-traded note (TVIX), which rises when the broader market fell. It returned to the Top 10 for the first time since March.

Here’s complete list for the top symbols in May:

1. Apple (AAPL): The smartphone giant held its No. 1 position from April.
2. SPDR S&P 500 ETF (SPY): The market-tracking fund remained No. 2.
3. ProShares UltraPro QQQ (TQQQ) : The leveraged Nasdaq-tracking fund climbed from ninth place in April. It’s up from 15th in March.
4. Amazon.com (AMZN): The e-commerce giant slipped one spot in May.
5. Tesla (TSLA): The electric-car maker inched down from No. 4 as the shares slid to a new 2-1/2 year low.
6. Nvidia (NVDA): The chip company fell one position from the previous month.
7. VelocityShares Daily 2x VIX short-term exchange-traded note (TVIX): The long-volatility product jumped from 18th most active in April.
8. Roku (ROKU): The streaming-video company rose from 15th place as its shares broke out on strong results.
9. Advanced Micro Devices (AMD): The semiconductor stock slipped one notch from April.
10. Netflix (NFLX): The streaming-video company dropped from seventh place.

The following symbols exited the list:

• Boeing (BA): The aircraft maker dropped to 25th in May from 10th in April.
• Facebook (FB): The social-media giant declined from sixth place to 13th.