Unable to load data from flat file

I am new to BW. I am trying to load Master data from flat file with time dependent. I have created two time dependents Designation and Salary. In Flat file I have created DateFrom and DateTo.

In DateTo I have mentioned date as 9991231. but when loading the data I see in PSA table as 99.91.23.1.

I also dint see any records getting displayed when I execute the data.

Please help me in this.