Per Google, there have been 11 zero-days exploited in the wild in the first half of this year, which puts 2020 to be on par with 2019, when Google said it detected 20 zero-days

https://www.zdnet.com/article/google-eleven-zero-days-detected-in-the-wild-in-the-first-half-of-2020/

Google also published its first "Zero-Day Year in Review" report last week -- for the year 2019.

Here are some conclusions (1/2):

-Total 0-days: 20
-Most affected vendor: Microsoft (11)
-Google TAG and Kaspersky discovered more than half of all of 2019's zero-days

-No actively exploited zero-days have been found in Linux, Safari, or macOS since 2014, when Google began tracking this stat
-2019 was the first year when an Android zero-day was discovered
-63% of 2019's 0-day vulnerabilities were memory corruption bugs
-Same stat for 2020 H1