Confusion with the "Value" display under Distribution while profiling in SAP BOIS?

Hi All

      I am a newbie in the world of Data Governance(Profiling). I was trying out the profiling option  with some sample data in the SAP Information Steward tool. But I do have a doubt in the value displayed under the "Value" (in Distribution tab/Option) in the Profiling results as shown below in the following image(highlighted in the right):-

My "Adrs" field contains three digits numeric code values(no text field) and there are no data having 999Then why '999' is displayed there?

Please help me in understanding the concept