How to interpret Mc Cullan Volume Summation Index in this rallye?

Hi.

I was browsing fear n greed and stumbled upon the McCullan Volume Sumation Index. It shows „extreme fear“.

Does this mean the volume of rallying stocks is relativley low? Or does it mean that „bad“ stocks are sold heavily and volume of rallying stocks is normal?

https://i.imgur.com/7VO9ct2.jpg

Lets assume its a bull rallye: wouldnt the index be positive and +2000?