Problem understand about Time series

Hi Everyone. I want to ask about time series when import to Time series in FEFLOW. I have data annual rainfall of month of station with unit is (mm). I want to ask exactly how to convert data from mm before import to FEFLOW with set unit is mm/a. Because when i import data from .pow the value is only 0.000352 (no unit) and after assign time series for "in/out flow on top/bottom", the value show in the model is 128.6 with set unit (mm/a). And one more thing, If the total rainfall in 1 year is 1843,3 mm, when I build model with time step is 30 day, "in/out flow on top/bottom" use unit is mm/a for 30 day. After 1 year in model simulation, the total 12 step by 1843,3mm right? Thank for your answer!
Example: Help me convert data mm -> value before import to model!
Jan 128.6 mm -> ?
Feb 2.8 mm -> ?
Mar 1.6 mm -> ?
Apr 20 mm -> ?
May 9.4 mm -> ?
June 103.7 mm -> ?
July 14.0 mm -> ?
Aug 51.1 mm -> ?
Sep 235.5 mm -> ?
Oct 476.7 mm -> ?
Nov 462.0 mm -> ?
Dec 337.9 mm -> ?
Total -> ?

FEFLOW's internal unit for in/outflow on top/bottom is m/d (you can find all internal units in the Units section of the help system). Time series are interpreted based on the internal units, thus FEFLOW takes your values as m/d, showing them as mm/a accordingly. So you'll have to convert your time series to m/d. If you have mm/month you'd have to divide by the number of days in the month and multiply by 1000.

Thank you so much! I will try it and if have problem, please help me. Now i'm learning FEFLOW model and I want to know more than how the model simulation use time step. It will help me have exactly result when use this model! Best Regards!