What model to fit pseudo-logarithmic trend? I am dealing with a scatterplot where I am trying to figure out the relationship between two variables, but I have so far failed to identify what the best fit could be. The presence of zero values prevents me from using exponential and power law regression lines.

Zero values are not shown as the Y axis starts from 1, but they are present. My bad.

This is the scatterplot. To me it looks like this is some sort of logarithmic trend but I am not sure about it.

What model will best interpret this trend?
One option is to take a curve fitting approach. For example, scipy.optimize.curve_fit.
Something like this:
import numpy as np
from scipy.optimize import curve_fit

def f(x, a, b, c):
    &quot;Rough functional form of the data&quot;
    return a + b * (1 - np.exp(-c/x))

solution = curve_fit(f, c, y, p0=(3_500, 3_500, 200))