Short title: Time since survey to reach 1640 hours’ cordless phone use at the reported daily rate. Legend: This figure has a dual purpose. It shows both the reported time spent daily on a cordless phone (as a histogram) and the years since 2009 that it will take for participants to reach 1640 hours on a cordless phone at the reported rate of use (the black curved line). The curved line charts the critical rate of use over x years to reach 1640 hours’ use since the survey. The broken line indicates mid-2013 (4 years since the survey). All those to the right of where the lines cross (i.e. more than 60 mins/day) will have had ≥ 1640 hours’ exposure by mid-2013. This is equivalent to the top decile Interphone use. Previous use and cellphone use are not included. Only those who reported >15 minutes/day are shown in the histogram.