I came to notice this new portion of the referral system: in particular, the bar at the top. 

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The info button says that it counts purchases made after they 'trust' you (I have no idea what this means either) and leveling up past 50. Does this mean to get to all of the rewards, my referred person has to purchase in game? If not, does leveling give more than one point? And if so, what is the currency for points ratio, not $1 to 1 point I hope.

This does seem quite weird to be asking questions on this forum, likely for the first time in at least a year or two, but I recently just left the game for two or three months and am honestly just wondering what the heck this thing means.