https://www.reuters.com/article/us-deliveroo-ipo-stocks/deliveroo-dives-30-as-debut-of-the-decade-turns-torrid-idUSKBN2BN0SB >Shares in Deliveroo plunged by as much as 30% in their trading debut on Wednesday, slicing more than 2 billion pounds off the company's valuation in a blow to the food delivery group and the London market for initial public offerings (IPO).