$22 Billion: What Ad Blocking Might Have Cost Publishers During 2015

We spotted this stat today:

"Ad blocking estimated to cost publishers nearly $22 billion during 2015.
There are now 198 million active adblock users around the world.
Ad blocking grew by 41% globally in the last 12 months.
US ad blocking grew by 48% to reach 45 million active users in 12 months up to June 2015.
UK ad blocking grew by 82% to reach 12 million active users in 12 months up to June 2015."

Source