the SI was established. but did not reach a consensus. A small number of members argued strongly that the radian should be a base unit, but the majority felt the status quo was acceptable or that the change would cause more problems than it would solve. A task group was established to "review the historical use of SI supplementary units and consider whether reintroduction would be of benefit", among other activities. See also Angular frequency Minute and second of arc Steradian, a higher-dimensional analog of the radian which measures solid angle Trigonometry Notes References External links Natural units SI derived units Pi Units of plane angle