Private Function Ostersonntag(Jahr As Integer) As Date
Dim inta As Integer, intb As Integer, intc As Integer, intd As Integer
Dim inte As Integer, inth As Integer, intu As Integer, intv As Integer
Dim intw As Integer, intm As Integer, intn As Integer
Dim intTag As Integer, intMonat As Integer
 
inta = Jahr Mod 19
intb = Jahr Mod 4
intc = Jahr Mod 7
inth = Jahr \ 100
intu = inth \ 4
intv = (inth - 17) \ 25
intw = (inth - intv) \ 3
intm = (15 + inth - intu - intw) Mod 30
intd = (19 * inta + intm) Mod 30
intn = (4 + inth - intu) Mod 7
inte = (2 * intb + 4 * intc + 6 * intd + intn) Mod 7
 
intTag = 22 + intd + inte
If intTag > 31 Then
    intTag = intd + inte - 9
    intMonat = 4
 
    If intTag = 26 Then intTag = 19
    If intTag = 25 And intd = 28 And inte = 6 And inta > 10 Then intTag = 18
Else
    intMonat = 3
End If
 
Ostersonntag = DateSerial(Jahr, intMonat, intTag)
End Function