Can You Day Trade for a Living? What a Full-Population Brazilian Study Found

Study Overview

This study used Brazil's securities regulator (CVM) records to track the complete trading history of every individual who began day trading Brazilian equity index futures between 2013 and 2015, following their results through 2017.

Methodology Summary

Unlike survey-based research, this study used official regulatory trading records for the full population of 19,646 individuals who began day trading mini-Ibovespa index futures over the study window — not a self-selected or self-reported sample.

The researchers focused particularly on the roughly 1,551 individuals who persisted in day trading for more than 300 trading days — a group specifically chosen to represent traders who stuck with it long enough to potentially develop skill, rather than casual or one-time participants.

Key Findings

• 97% of the individuals who persisted for more than 300 trading days lost money, net of fees.
• Only about 1.1% earned more than Brazil's minimum wage from their trading, and only 0.5% earned more than the starting salary of a bank teller.
• The single best-performing individual in the study averaged about $310 per day, but with very high day-to-day variability (a standard deviation of roughly $2,560), meaning even the top result came with substantial risk.
• The researchers found no statistical evidence that traders improved or “learned” their way to profitability with more trading experience.

Limitations

• This study covers one country's futures market (Brazilian equity index futures) over one specific historical period (2013–2017); results may not directly generalize to day trading individual stocks or day trading in other countries, though broadly similar loss patterns among short-term traders have been documented in other markets.
• The study specifically isolated traders who persisted for 300+ days — it doesn't tell us about outcomes for people who tried day trading briefly and stopped.
• It measures whether individuals made money, not why — the paper doesn't fully separate out how much of the loss came from trading costs versus poor market timing versus other factors.

Practical Meaning

This is one of the more rigorous pieces of evidence on day trading outcomes because it's based on complete regulatory records rather than self-reported results, and it specifically studied people who stuck with day trading long enough to have a real chance to develop skill. The finding that persistence didn't correlate with profitability is a meaningful data point for anyone considering day trading as a primary income source.

Related Reading

• Day Trading Basics
• Is Day Trading a Good Way to Make Money?