Calculate height from tangent of a point on the circumference of a circle

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I have a mechanical press which uses rotary eccentric gears and plungers to translate rotation into a linear movement of fixed length, or stroke. The machine moves linearly to a maximum distance of 500mm.

I've drawn the system out in CAD, to scale, and measured the heights manually.

CAD Drawing with measurements

Measurements:

Angle (degrees) Distance (slide Stroke mm)
0 0
10 4.03
20 16.11
30 32.59
40 58.23
50 87.85
60 124.57
70 162.01
80 205.55
90 250

What i've been trying to figure out, is the mathematical relationship to calculate that stroke (height from the tangent of the circle i think?) for any angle of the circle.

I can obviously see the relationship between radius and height, but can't figure out how to incorporate the angle into the equation.

By graphing stroke against angle, I see it trends a sine wave:

Sine Wave

but doing something like 500 * sin(theta) doesn't get me near.

Looking for some feedback on how to calculate this measured value please