The Hirsch h-index is widely used to measure a researcher’s major publications. It has the advantage of being easy to compute. However, it increases steeply with time and therefore does not allow a comparison of young and mature researchers. We find that if the h-index is divided by the number of decades since publication of the researcher’s first paper, the result is statistically constant with age. Then the resulting index can be compared for young and old researchers. Its accuracy is the same as that of the h-index and is as easy to compute as the h-index.
Keywords: Publication indexes ; Astronomy; Hirsch h-index