By the time Callaghan took over, the average interval had been increased to a little over two years.
The average interval was somewhere between twelve and thirteen months.
Riverside is unique in its way that eruptions seldom occur at the average interval for any given time.
The slip rate has been about 1 mm per year suggesting an average interval between earthquakes of 3000 years.
The average interval between litters is about four years.
The line is planned to have an average interval of six minutes between each station.
The average interval between births is 34 months.
This route has average intervals of 15-20 minutes outside of rush hour.
But as recently as 1950, the average interval between eruptions was 62 minutes.
The average interval here has been 20,000 years, and 70,000 have passed since its last eruption.