New research posits that without fancy accounting, half of unicorn startups would lose their horns.

What are Silicon Valley’s darlings really worth? Two business school professors took a sample of 116 “unicorns,” companies with valuations of $1 billion or more, and calculated their fair value—using the price of preferred shares to value shares that don’t have those rights. Their conclusion: Half the “unicorns” were worth less than $1 billion, and more than a dozen were overvalued by 100%.