A variant of the h-index to measure recent performance
  The predictive power of the h-index has been shown to depend for a long time on citations to rather old publications. This has raised doubts about its usefulness for predicting future scientific achievements. Here I investigate a variant which considers only the recent publications and is therefore more useful in academic hiring processes and for the allocation of research resources. It is simply defined in analogy to the usual h-index, but taking into account only the publications from recent years, and it can easily be determined from the ISI Web of Knowledge. 
Michael Schreiber
cs.DL physics.soc-ph