[College Physics, Current Measurements] Lab Project Need Help

I am using a Keithley 485 Autoranging Picoammeter to measure some small currents by passing 10V across a highly resistive bar. The ammeter shows a current of 0.352 microamperes when the range is set to 20 microamps and 3.25 microamperes when the range is 200 microamps.

What does this mean? Why does changing the range literally change the current by a factor of 10? Am I reading the current wrong?