Right now you can only set a value for hour (or parts of hour) for Offset values.
For example for a 1-minute offset you have set (1/60th parts of 1) - 1 has the value of 1 hour.
For more fractional parts you have define even smaller parts.
Also you cannot set offset values for year/month/days
Please improve this by implementing offset values for year/months/days etc in seperate input fields.