Millennial investors have a history of loading up on retail stocks before Black Friday (AMZN, WMT, BBY, M, JCP)

Black Friday is one of the biggest days of the year for retailers.
Millennials on the stock trading app Robinhood have been mostly bullish on retail companies ahead of the major holiday.
Trading volumes are usually higher in the week before the holiday.

Black Friday is one of the biggest shopping holidays in the US. As some Americans wrap themselves in coats and scarves to brave the cold of the Black Friday sales, investors on the stock trading app Robinhood are buying and selling retail companies to try and cash in on the holiday.

Last week, investors on the Robinhood app, which is popular with millennials, were trading retail stocks 50% more than usual. The only other times retail companies tend to trade as frequently have been during quarterly earnings releases, Sahill Poddar, a data scientist at Robinhood, told Markets Insider.

Poddar said he expects trading volume for retail stocks to spike again this year ahead of Black Friday. Robinhood users tend to be more bullish around this time of year, so he thinks they will be more inclined to go on buying sprees than cash out their winnings.

Poddar shared some trading trends from last year's holiday to shed some light on what could be coming this week.

JCPenney was one of the most traded retail companies on the platform on Black Friday last year. Robinhood users traded the stock 5 times more than the prior trading day, Poddar said. That doesn't mean traders were bullish on the company though, as there was an equal amount of buying and selling. The stock fell about 2.91% during Black Friday last year.

Robinhood users were particularly bullish on Best Buy last year and bought the stock 60% more often than they sold it. Volume was not particularly heavy in the days leading up to Black Friday, though, Poddar said.

Two of the largest retail companies in the world, Amazon and Walmart are going toe-to-toe in the retail space. Amazon bought Whole Foods to add groceries to its product lineup and move into the physical retail space while Walmart is upping its online game with offerings like in-store pickup and easy returns.

Robinhood users were equally bullish on the two companies before Black Friday last year and bought shares of each 30% more often then they sold them. Trading volume for Amazon was twice as high in the week leading up to Black Friday last year. Volume for Walmart spiked 80% in the same time period.

The New York Stock Exchange will be closed on Thursday for Thanksgiving, but will be open from 9:30 AM to 1 PM on Black Friday.