If Airbnb is 10% of the market and increases revenue by 89% whilst all others stay flat, that only requires an 8.9% increase in the market. Of course, if that

If Airbnb is 10% of the market and increases revenue by 89% whilst all others stay flat, that only requires an 8.9% increase in the market. Of course, if that happens, others would be losing "share", albeit not shrinking in absolute terms. But, in fairness, the article seems very wishy washy in its definition of "market share".