Pinterest shares tumble as profit seen elusive

(Reuters) - Pinterest Inc's shares slumped as much as 17% on Friday after the online scrapbook company's disappointing annual forecast shook investors' faith in its ability to turn in a profit soon.The fall in shares after Pinterest's first quarterly results as a public company took some of the shine off its successful stock market debut last month. Up to Thursday, Pinterest's shares had risen 62% since their April 18 opening.The company, which gets revenue through advertisements that are placed..