Postgresql numeric and decimal is automatically rounding off
It seems to be the default behaviour of SQL Workbench, have a look at this article:

How do I change the resolution or scale of decimal data type on SQL Workbench.

Quoted from the article:


  Normally, SQL Workbench doesn't display the decimal data with the full
  scale. By default the scale is 2. We can change the scale by the
  setting.





  Solution
  
  
  Open Data formatting settings. SQLWorkBench -> Preferences ->Data formatting
  Change Decimal digits The default is 2. In this case, it should be at least 11.
  


And according to SQL Workbench manual about Data formating:


  Decimal digits
  
  Define the maximum number of digits which will be displayed for
  numeric columns. This only affects the display of the number, not the
  storage or retrieval. Internally they are still stored as the DBMS
  returned them. To see the internal value, leave the mouse cursor over
  the cell. The tool tip which is displayed will contain the number as
  it was returned by the JDBC driver. When exporting data or copying it
  to the clipboard, the real value will be used.
  
  If this value is set to 0 (zero) values will be display with as many digits as available.


(Bold is mine)