I created a simple CSV file with fractional hourly values. I created a full 8760 hours worth, saved the CSV file locally on my Windows 7 machine, and then referenced this file in EnergyPlus, in a Schedule:File definition.
After running the simulation, when I compare the output hourly fractional values to the CSV file, I find what look like EnergyPlus random insertions, and sometimes deletions, which cause the output not to match the input.