Yeah, there are some bond ETFs, SPY and some sector ETFs like home construction, biotech, semiconductors... but it's not a broad diversification. That's why I asked why did you chose biotech for instance but not finance ETF...

Ok, it seems that you are quite experienced at ETFs picking but I'm not unfortunately. I've tried to select ETFs but not very successfully. Let's imagine I'll continue to try ETFs, plug them into asset list and run Z9 system. Eventually, I'll come up with a great combination that will produce great results. However, I'm concerned about statistical bias and not so great results in live trading (if i'll try for a long time, I'll find best performing ETFs in a backtest). What approach do you recommend in this case for ETFs picking?