I have previously written about Unicorn Market Cap and Industry towns in 2019 and 2020. Over the last 8 months the number of tech startups worth $1B or more ("unicorns") has grown by 43% from 487 Unicorns to 701. This is almost double the 361 unicorns in June 2019 (!).
Caveat emptor: data from CBI is updated/reconciled over time, so very recent unicorns may not be included yet. However this provides a directional view.... Raw data here.
Here is the full list for the USA