SDLK_KP_PERIOD and SDLK_KP_DECIMAL redundancy?

On my mac’s keyboard, the keypad’s period is reported as SDLK_KP_PERIOD. On my windows computer, it’s reported as SDLK_KP_DECIMAL. Is there a reason these are different? It seems a bit redundant to me to have both SDLK_KP_PERIOD and SDLK_KP_DECIMAL.

Is there a reason for it?