If I count this correctly, the damage is 0.9 £ per person per month. So this is what the claimant thinks should be an average and fair monthly compensation for being a FB user for that time.
[1] https://seekingalpha.com/article/4410715-facebook-is-running...
Highly doubt this would be in the "cost of doing business category"
2.3 billion GBP.
44 million people.
From October 1st to December 31st is 3 months. Followed by all of 2016 through all of 2019, so 4 times 12 months.
51 months total.
((2.3 * 10^9)/(44 * 10^6))/51