PC-Lab2000se Translating Export Data to Real Voltages

When I save the data from the transient recorder, the voltages appear as a list of 8 bit words in decimal form (0-255) and says that 32=0.2V. Is this linear (64=0.4V etc) or exponential? If it is exponential, what voltage does 0 represent?

It is linear (32=0.2V, 64=0.4V etc).