The data is non-linear, so the formula is not straightforward.
Here is a stab at part of the solution. This works for the max, min and avaerage
You need to substitute the non-linear formula for the "X"

=IF(A1=MIN($A$1:$A$30),0,IF(A1=MAX($A$1:$A$30),100,IF(A1=AVERAGE($A$1:$A$30),50,"X")))