Probability distribution functions for solar wind speed w for accelerated and decelerated CMEs with a kernel density ρ on the y-axis. Left: w PDFs for accelerated CMEs with Optimal Fit label. Note that the normal and student-t distributions overlap with each other. Right: w PDFs for decelerated CMEs with Optimal Fit label. All three distribution functions overlap with each other. The overlapping of functions is evident through RSS values.