/diy/ - Do It Yourself

I need help interpreting this datasheet for a pressure sensor. Is full-scale span the voltage range of the sensor? So for the SX100, at 0 psi it would output 100 mV, and at 100 psi it would output 200 mV. Is that correct?
There's a foot note that says
>Note 9: Full-scale span is the algebraic difference between the output voltage at full-scale pressure and the output at zero pressure. Full-scale span is ratiometric to the supply voltage.
What does it mean that full scale down is ratiometric to the supply voltage?