When broadcasting licenses were first granted in 1921, all stations were assigned a common wavelength of 360 meters (equivalent to a frequency of 833 kHz). This of course would mean that no two stations in the same area could be on at the same time. In December 1921, a second wavelength, 485 m (corresponding to a frequency of 619 khz) was assigned for some special types of broadcasts like weather reports and farm information. But rather than assigning some stations to one frequency and some to the other, the division was made by content, so a station would switch frequencies when it was time to give a weather report.