Función demasiado larga

Estiamdos:
Tengo un reporte que quiero traspasar las fórmulas a Excel y tengo el
siguiente problema, tengo una fórmula que excede la capacidad en el
excel, como puedo optimizar esta fórmula, ejemplo :

if stock_0>(entradas_120+mes-0+mes-30+mes-60+mes90) then
(entradas_120) else (Stock_0-(mes-0+mes-30+mes-60+mes90)

Serí aalgo así :
=SI($T11>($J11+
SI($R11>$T11,$T11,$R11) +
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))) +
SI($T11>($N11+SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))),
$N11,($T11-((SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))))))) +
SI($T11>($L11+
SI($R11>$T11,$T11,$R11) +
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))) +
SI($T11>($N11+SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))),
$N11,($T11-((SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))))))
),$L11,($T11-
(SI($R11>$T11,$T11,$R11) +
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))) +
SI($T11>($N11+SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))),
$N11,($T11-((SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))))))
)))
), $J11,
($T11-(
SI($R11>$T11,$T11,$R11) +
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))) +
SI($T11>($N11+SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))),
$N11,($T11-((SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))))))) +
SI($T11>($L11+
SI($R11>$T11,$T11,$R11) +
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))) +
SI($T11>($N11+SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))),
$N11,($T11-((SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))))))
),$L11,($T11-
(SI($R11>$T11,$T11,$R11) +
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11)))) +
SI($T11>($N11+SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))),
$N11,($T11-((SI($R11>$T11,$T11,$R11)+
SI($T11>($P11+SI($R11>$T11,$T11,$R11)),$P11,($T11-(SI($R11>
$T11,$T11,$R11))))))))
)))
))