I have run probit and logit regression analysis for a model, where the dependent variable is 'Purchase' which takes the value of 1 for purchase, else zero. The independent variable is the log of distance from the highway. The unit of distance from the highway is in miles. I have calculated the marginal effects:

I have interpreted the effect as:
A one-mile increase in travel distance from the highway increases the chance of purchase by 0.0099Xln(1.01) = 0.000098 percent (probit regression).
Does my interpretation look correct? If not, how I should explain?