Krakatoa: Particles and time


Hello everyone!
I have a small and maybe trivial question:
I have a Krakatoa PRT file with only position and ID channel.
from it I would like to consider the single particle trajectory and calculate Velocity, Acceleration, Curvature, Torsion but to do it I would need to know the particle´s position in different moments.
with this I mean for example something like:
vel= pos(at time t1)-pos(at time t0) / (t1-t0)
acc=vel(at time t1)- vel(at time t0) / (t1-t0)

my problem is that I don´t know any way to ask Magmaflow to"look" in the past for the old position of a certain particle.
The only workaround could think is to clone my PRT and offset it in time than consider the same particle in the original and “offset” PRT.
does anyone know a better method?
Thank you very much