The recent decline in Nifty below the psychological 22000 mark has raised concerns among investors, especially after SEBI Chairperson Madhabi Puri Buch's remarks on stretched valuations of small- and mid-cap stocks. Attention now turns to the NSE Small-cap index and the Nifty's support levels. Meanwhile, the commodities market sees a surge in WTI Crude and copper prices. Investors await the US PPI data and the upcoming FOMC meeting. Trading strategy suggests buying Nifty between 21800-21850 with targets at 22200/22530 and Bank Nifty between 46500-46600 with targets at 47500/47800.