With reference to this regression line:
https://dl.dropboxusercontent.com/u/46186972/regression_line.gif
As shown in the bottom-right of this chart, the formula for the black regression line is:
y = 0.075ln(x) + 0.2775
How can I write this formula in Microsoft Excel, so that I can calculate y for any given value of x ? (I tried calculating it using Excel help, but it did not give me the correct y values shown in the regression line chart linked above).