I'm curious what's going to inevitably eat into that potential margin. The most profitable large scale businesses are Visa and Facebook. After the corporate tax change, both should get near 50% net income margins (Visa is at 44% last quarter; Facebook was at 46%). I could see some of it getting competed away vs Lyft, given back to consumers in lower fares. Some to typical bloat with scale & age. Perhaps higher local taxes on their business, as the cities they make all their money in will hit them that much more if they're not employing drivers. And of course those millions of vehicles will have a high cost in terms of maintenance, replacement, vandalism, etc.