IPO date: March 29, 2019 IPO value: $24 billion Revenue: $2.2 billion Price-to-sales ratio: 11.4xExpected IPO date: April 2019 Estimated IPO value: $120 billion 2018 revenue: $11.3 billion, the company said earlier this year. Price-to-sales ratio: 10.5xExpected IPO date: 2019. Pinterest filed its S-1 with the Securities and Exchange Commission in March. Estimated IPO value: $12.3 billion, according to a Wall Street Journal analysis of Pinterest's S-1. Revenue: $755.9 million Price-to-sales ratio: 16.3xExpected IPO date: 2019, but the co-founder said in comments to Business Insider in March that it may not go public this year. Estimated IPO value: $31 billion Estimated revenue: $2.76 billion Price-to-sales ratio: 11.2xExpected direct listing date: The first half of 2019, according to The Wall Street Journal, citing people familiar with the company's plans. Slack confidentially filed its S-1 with the Securities and Exchange Commission in February. Estimated direct listing value: Slack was most recently valued at $7 billion Estimated revenue: $221 million Price-to-sales ratio: 45.3x Expected IPO date: As soon as the second half of 2019, according to The Wall Street Journal, citing people familiar with the matter. Estimated IPO value: $41 billion Estimated revenue: $750 million Price-to-sales ratio: 54.6x IPO date: March 1, 2017 IPO value: $24 billion Revenue: $404.5 million Price-to-sales ratio: 59.3xIPO date: September 18, 2014 IPO value: $168 billion Revenue: $8.44 billion Price-to-sales ratio: 19.9xIPO date: November 6, 2013 IPO value: $14.2 billion Revenue: $639.8 million Price-to-sales ratio: 22.2xIPO date: May 17, 2012 IPO value: $104 billion Revenue: $3.711 billion Price-to-sales ratio: 28xIPO date: September 23, 1998 IPO value: $715 million Revenue: $14.922 million Price-to-sales ratio: 47.9xIPO date: May 14, 1997 IPO value: $413 million Revenue: $15.75 million Price-to-sales ratio: 26.2xIPO date: April 11, 1996 IPO value: $334 million Revenue: $1.41 million Price-to-sales ratio: 238.6xIPO date: August 8, 1995 IPO value: $927 million Revenue: $5.4 million Price-to-sales ratio: 171.6xTesla analysts are piling on after disappointing delivery numbers sent the stock plunging