I know the that the red markers show your website dropping in the Alexa and the green markers mean that your rankings improved, but what do the actual numbers mean?
For example, if your website shows a red mark of 1,000,000, does that mean that your website dropped from the 1,000,000th position or that it fell 1,000,000 rankings?
It is based on rankings.
So if yesterday I was in position 1 and today I am in position 4, there will be a red minus 3 symbol.
It means the former, but Alexa is not something you should ever use for any form of analysis or analytics.
The red markers show your website dropping in Alexa rankings and the green markers mean that your rankings have improved.