Calculating fields - add start and end coordinates of line features to table

Hello everybody,

Since a wile I am serching a way to solve a problem but cant get to any result.
What I want to do is to add koordinates of the startpoint and endpoint of a line-feature to its attribute table.
In my project I have to traw a great number of lines (representing power grid) so I manually added 4 fields (StartX, StartY, EndX, EndY). Is there any toold in arc toolbox that can help me calculate the koordinates for those 4 fields. Manually adding the data would be very time consuming. For better understanding i attached a photo with a sample of the grid (green line) and its attribute table.


Thanks for any kind of help
Alex

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