Shares of new-age companies that have gone public so far this year have tumbled from their peaks as analysts and market veterans continue to raise concerns about market valuations.Shares of CarTrade Tech Ltd. to FSN E-Commerce Ventures Ltd., operator of Nykaa, have retreated from their post-IPO highs by 10-30%. And Paytm's parent One97 Communications Ltd.'s decline on listing day, one of the worst market debuts, would have only turne...