Evolution rates since 3 April 2003 based on number of Tv substitutions at 2- or 4-fold degenerate sites (N = 257) and estimated time since PV2 Sabin if linear rate.

*Days since collecting sample yielding #783.∧Linear regression coefficient.#Number of nt changes/site/year.¤y – axis cutting point.@For any time point with more than one identical p-difference, the value included in calculation only once.&Representatives of of all lineages and some orphan strains included.NR, not relevan.