Piper Jaffray has been polling teenagers about their spending habits twice a year since 2001, hoping that getting inside their minds now is key to predicting spending trends.

Results of the Minneapolis investment bank's most recent survey offered one giant takeaway: Half of all teens rank Amazon as their preferred website.

In fact when it came to e-commerce, Amazon was 10 times more popular than its closest competitor, Nike.

Today's teens are the first to grow up in a completely digital world, and are on track to be the most educated generation yet, according to Pew Research. In Piper's survey, 83 percent of teens said they had an iPhone.

Currently identified by the lackluster name of Generation Z, those born between 1997 and 2012 are the most racially and ethnically diverse group in America's history. Pew has described them as having a more liberal set of attitudes than millennials and as being more open to emerging social trends.

Piper's spring survey aimed to capture that. The research, which includes responses from 8,000 teens from 47 states, for the first time asked respondents whether they preferred to identify with a gender-neutral pronoun "they" rather than male or female. About 3 percent said they did.

The firm also for the first time asked teens what it called an "unaided question" in which they were asked to name a social or political cause they most cared about. Nine out of 10 chose to answer. Immigration and climate change ranked highest, followed by racism, gun control and gender equality. The average age of respondents was 16.

The company estimates that those between 13 to 19 accounted for more than $75 billion in spending power at the end of last year. Their spending patterns and habits have been shaped by the dynamic, digital world that has defined their lives, Piper said.

Thirty-eight percent said Netflix leads their daily video time, followed by YouTube at 32 percent and traditional TV at 14 percent. Video game consumption hit an all-time high.

The popularity of eBay hit an all-time low of 1 percent in the survey, though it has never been a strong contender among this group.

Females spend about a quarter of their discretionary dollars on clothes, while food is the largest category for males.

When it comes to social media, Instagram is growing in popularity and is accelerating among younger teens, Piper found. Teens use it more frequently, but they say they like Snapchat better.

Jackie Crosby • 612-673-7335

Twitter: @JackieCrosby