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27th feb nifty broke the crucial 25400 support level (which earlier was resistance level) after multiple hits. And within 24 hours the US-Israel Attack on Iran news surfaced around 11:49 AM IST on 28th Feb.
This again solidifies a theory that price moves first , news follows later. Be it positive or negative news. Be it stock specific, sector indices specific or economy indices.
Be it microcaps, small caps , midcaps , largecaps.
News affects Stock Prices. It seems Stock Prices move first and news follows later. Which makes sense as big, prudent, resourceful investors get information quickly and load/unload their positions quickly which reflects in price first then news comes out.
Here is Rakesh Jhunjhunwala explaining the effect of News on Stock prices :