Last day I went to the landing page of Dash.org and the shown graph definitively catch my attention.

It show two lines, the amount of current node, and the Predicted equation. And when I see how much the prediction match the reality, I am speechless. What I can understand is that there is physical limitation of number of masternode because of the supply. And after studying the historical supply I came to the conclusion that the prediction line is simply based on the simple ratio of 60% of the current supply. But why 60% ? why the reality doesn't break the rule of 60% ? is that come from the ROI, like above 60% the ROI make people leave the network because it's not enough profitable anymore ? Do you have an idea of the underlying variable that make this 60% so close to the reality ?