For Each Cell In task
Randomize

The Randomize statement should not be executed more than once for the
lifespan of the object that is executing your code. Doing so more often
actually makes the data less random than if Randomize is only run once. For
so few colors, and the probable use the OP wants to use the Rnd function
for, it will more than likely not matter here, but it is the concept that is
important to know. I can't demo it within Excel because I am not aware of an
available object where I can set the color of individual pixels (like a
PictureBox control in the compiled version of VB for those who have worked
with that language); however, I do have a VB program that demonstrates this
fact visually.

For those of you having access to the compiled versions of VB5 or VB6, here
is posting I have offered over in the compiled VB newsgroups in the past
that demonstrates this fact...

Running Randomize multiple times ends up producing a less random set of
numbers. To see the problem visually, use this code (which is a modification
of a routine Bob Butler once posted). Start a new project and put two
PictureBox'es on your Form (use the default names for everything and
placement of the PictureBox'es is not important). Paste the following code
into the Form's code window. The PictureBox on the left results from using
Randomize only once, the one on the right uses it repeatedly. Both
PictureBox displays are produced from the same looping code with the only
difference being the use of the Randomize statement Ignoring the pronounce
vertical areas (not sure what that is, probably some kind of boundary
rounding problem), for which one does the distribution of colors look more
"random"?

Rick

Const SCALESIZE = 3

Private Sub Form_Load()
Picture1.ScaleMode = 3
Picture2.ScaleMode = 3
Randomize
Picture1.Move 0, 0, _
128 * Screen.TwipsPerPixelX * SCALESIZE, _
128 * Screen.TwipsPerPixelY * SCALESIZE
Picture2.Move Picture1.Width, 0, _
128 * Screen.TwipsPerPixelX * SCALESIZE, _
128 * Screen.TwipsPerPixelY * SCALESIZE
Me.Width = 2.02 * Picture1.Width
Me.Height = 1.1 * Picture1.Height
End Sub

Private Sub Picture1_Paint()
Dim i As Long
Dim j As Long
Dim colr As Long
Dim bitmask As Long
For i = 0 To Picture1.ScaleHeight Step SCALESIZE
For j = 0 To Picture1.ScaleWidth Step SCALESIZE
colr = Rnd * 16711680
Picture1.Line (j, i)-Step(SCALESIZE, _
SCALESIZE), colr, BF
Next j
Next i
For i = 0 To Picture2.ScaleHeight Step SCALESIZE
For j = 0 To Picture2.ScaleWidth Step SCALESIZE
Randomize
colr = Rnd * 16711680
Picture2.Line (j, i)-Step(SCALESIZE, _
SCALESIZE), colr, BF
Next j
Next i
End Sub