=DATE(YEAR(A1),MONTH(DATE(YEAR(A1),MONTH(1),DAY(1)))+((INT(((MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))+(MOD((32+2*(MOD(INT(YEAR(A1)/100),4))+2*(INT((MOD(YEAR(A1),100))/4))-(MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))-(MOD((MOD(YEAR(A1),100)),4))),7))-7*(INT(((MOD(YEAR(A1),19))+11*(MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))+22*(MOD((32+2*(MOD(INT(YEAR(A1)/100),4))+2*(INT((MOD(YEAR(A1),100))/4))-(MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))-(MOD((MOD(YEAR(A1),100)),4))),7)))/451))+114)/31))-1),DAY(DATE(YEAR(A1),MONTH(1),DAY(1)))+(((MOD(((MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))+(MOD((32+2*(MOD(INT(YEAR(A1)/100),4))+2*(INT((MOD(YEAR(A1),100))/4))-(MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))-(MOD((MOD(YEAR(A1),100)),4))),7))-7*(INT(((MOD(YEAR(A1),19))+11*(MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))+22*(MOD((32+2*(MOD(INT(YEAR(A1)/100),4))+2*(INT((MOD(YEAR(A1),100))/4))-(MOD((19*(MOD(YEAR(A1),19))+(INT(YEAR(A1)/100))-(INT(INT(YEAR(A1)/100)/4))-(INT(((INT(YEAR(A1)/100))-(INT(((INT(YEAR(A1)/100))+8)/25))+1)/3))+15),30))-(MOD((MOD(YEAR(A1),100)),4))),7)))/451))+114),31))+1)-1))