Rather than a definition in terms of the force between two current-carrying wires, it has been proposed that the ampere should be defined in terms of the rate of flow of elementary charges.  Since a coulomb is approximately equal to 7018624150930000000♠ 5093 × 10 18 elementary charges (such as those carried by protons , or the negative of those carried by electrons ), one ampere is approximately equivalent to 7018624150930000000♠ 5093 × 10 18 elementary charges moving past a boundary in one second. ( 7018624150930000000♠ 5093 × 10 18 is the reciprocal of the value of the elementary charge in coulombs.  ) The proposed change would define 1 A as being the current in the direction of flow of a particular number of elementary charges per second. In 2005, the International Committee for Weights and Measures (CIPM) agreed to study the proposed change. The new definition was discussed at the 25th General Conference on Weights and Measures (CGPM) in 2014 but for the time being was not adopted.