Tengo dos columnas de datos: Member Time A 09/24/2015 09:48:36 A 09/24/2015 09:47:40 A 09/24/2015 10:11:06 A 09/24/2015 10:08:47 B 09/24/2015 10:28:45 B 09/24/2015 10:29:49 B 09/24/2015 10:30:12 B 09/24/2015 10:30:46 A 09/24/2015 10:33:59 A 09/24/2015 10:31:27 Digamos que estos datos comienzan...