u/Equivalent-Cable9992

I’m testing a strategy across a basket of futures/assets. One of the assets shows a strong equity curve in recent years, but the older part of the backtest is almost flat or weak.

Is this usually a sign of overfitting, market regime change, bad data/rollover issues, or could this be normal for certain short-term strategies?

I’m trying to understand whether this means my code is wrong, or whether the edge only appeared in more recent market conditions.