What you can do for this case is graph the data in a computer program, for example, excel and look for the trend line of the function.
For this case, the function has a logarithmic behavior, therefore, we choose a linear logarithmic trend.
The function that best suits the problem is:
y = 1.4004ln (x) + 0.2158
The value of R ^ 2 indicates the accuracy of the function
R² = 0.9691
For R ^ 2 = 1 the function is completely accurate.
We note that in that case R² = 0.9691, the function chosen has a good approximation.
For this case, the function has a logarithmic behavior, therefore, we choose a linear logarithmic trend.
The function that best suits the problem is:
y = 1.4004ln (x) + 0.2158
The value of R ^ 2 indicates the accuracy of the function
R² = 0.9691
For R ^ 2 = 1 the function is completely accurate.
We note that in that case R² = 0.9691, the function chosen has a good approximation.