MSD m.s.d. analysis procedure?

Does anybody out there have a procedure for doing mean squared displacement analysis in IgorPro? I already have a set of 2D trajectories over time, so I don't need particle detection/tracking capabilities. Sorry if this is a bit lazy, but I just wondered if somebody already had working code that they are willing to share to extract msd for various lag times. it would save me writing something myself or converting the MATLAB version to IgorPro. Hopefully somebody can help.

Thanks,
Steve