aldagaiaren balioak bakanak direnean.
Adibidez: Urizarko osasun-etxeko sendagile batek, 2011ko ekainean, eguneko zenbat gaixo artatu dituen: 20, 18, 21, 17, 20, 22, 21, 20, 18, 17, 22, 21, 16, 21, 20, 22, 21, 19, 22, 20, 18, 19, 20, 22, 15, 20, 18, 17, 16, 18.