# How nifty50 PE is calculated

I just could not figured out how Nifty’s PE is calculated. I am just in confusion, on 12th Jan 2017 Nifty closing index was 10681.25 and PE was 27.28, now today 15th Jan 2017 Nifty closed on 10,741.55 (0.56% higher) but its PE is 27.06. Can anybody explain this discrepancy? (Have earnings increased that high in a day to justify??).

I would like to invite @Karthik sir to shed some light on this question.

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It definitely will be based on the earnings reported by the constituents of NIFTY and could have been adjusted based TTM EPS. The exchange would have a better access to this information and technology to arrive at precise figures, so I don’t think there is a discrepancy here. INFY, which has a weightage of 5.44% in NIFTY, reported earnings after closing time on Friday (12/Jan), which reported quite good EPS change because of on tax reversal benefit, so this could be the reason of the change in PE.

And @Sandeep7 , @sabyasachi_sadhu is not asking about how to calculate Put option greeks or premium! He is referring to PE which is the price-to-earnings of NIFTY.

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Thanks @saiography, yes I too believe that earnings are calculated on the basis of weight-age of the particular scrip and if index is hiked by those particular scrips then Nifty might be using only the earnings of those scrips responsible for the hike.

Everything is explained in this article by Dev Anand. Link:- https://www.stableinvestor.com/2016/01/changes-index-constituents-sensex-nifty.html

Was there a change in NIFTY 50 constituents on 12th Jan 2018?

The short answer is none. But again even without new entrants the reported earnings were quite high for that particular day (How earnings are calculated on daily basis?). So the OP(that’s me) has already answered that question in my question only.

PE ratio of each stock varies each day , but weightage of each stock remains the same …

If there are variances in PE of each stocks , overall PE will vary even if the nifty 50 doesnt move …