Wrong.
If it's a matter of directly proportional, then all you need is one single point.
Look at the first one:
x = 20,000
y = 1,000
y/x = 1,000/20,000 = 0.05
y = 0.05 x
The constant of proportionality is 0.05 (5 percent).
Look at the other points just to check it out and see if it holds water:
x = 1,500
y = 30,000
x/y = 0.05 yes !
x = 2,000
y = 40,000
x/y = 0.05 yes !
It checks out.
The constant of proportionality is 5% for all points in this table.
