- We see the difference (i.e. the derivative ~ (IO(t+10) - IO(t))/10) is a linear function of the initial size IO(t).

Input := 

p1 = ListPlot[data,PlotStyle->{PointSize[.02]},
AxesLabel->{"IO(t)", "(IO(t+10)-IO(t))/10"}]
Output =

-Graphics-