How can I reduce the formula?

[ME_Webdesign]

Hello, I want to take data from a user, it has to be the last data.
I created this, and it works, but I don’t want to do something so complex because I need to use it many times:

IF([_THISROW].[MES DEVENGADO]<12,

SUM(SELECT(LIQUIDAR_UNIDAD[ADEUDA FO],
AND(
[ID_UNIDAD]=[_THISROW].[ID_UNIDAD],
[AÑO DEVENGADO]=[_THISROW].[AÑO DEVENGADO],
[MES DEVENGADO]=[_THISROW].[MES DEVENGADO]-1
)
)),

SUM(SELECT(LIQUIDAR_UNIDAD[ADEUDA FO],
AND(
[ID_UNIDAD]=[_THISROW].[ID_UNIDAD],
[AÑO DEVENGADO]=[_THISROW].[AÑO DEVENGADO]-1,
[MES DEVENGADO]=[_THISROW].[MES DEVENGADO]
)
))

)