If you're going to value anything using a multiple, you've got to pick the right multiple. There is a way of using ratios to get a quick value of a company, but you need to use the right one ...

Ivashina, Victoria, and Henrik Boe. "Primer on Multiples Valuation and Its Use in the Private Equity Industry." Harvard Business School Background Note 218-017, July 2017. (Revised January 2020.) ...