Assuming data is in A2:B7, and your values of 103,2% is in E2, then try:

=INDEX($B$2:$B$7;MATCH(MIN(ABS($A$2:$A$7-E2));ABS($A$2:$A$7-E2);0))

adjust ranges and/or function names to suit.. and confirm with CTRL+SHIFT+ENTER not just ENTER and copy down.

FYI, in Polish:

=INDEKS($B$2:$B$7;PODAJ.POZYCJĘ(MIN(MODUŁ.LICZBY($A$2:$A$7-E2));MODUŁ.LICZBY($A$2:$A$7-E2);0))