Achei, pelo menos aqui deu certo. Óbvio que a opção "Preservar a formatação da célula ao atualizar" deve estar marcada. A partir daí, deve-se aplicar a formatação com a opção da Aba: Análise de Tabela Dinâmica/Grupo: Ações/Opção:Selecionar/Habilitar Seleção. Aquilo que for selecionado com a função "Habilitar Seleção" manterá o formato. O chato é que às vezes seleciona toda uma coluna e às vezes seleciona só uma cela. Aí tem que fazer cela a cela, mas deu certo aqui.

Actually, you need to format each field data type, and make sure the whole pivot table settings are set to retain the formatting when refreshed. 

You can use the VB script:"Private Sub Worksheet_PivotTableUpdate(ByVal Target As PivotTable)"
and put all formating information in between. This routine will be carried out after changing Pivottable content
For example:" With Selection
.HorizontalAlignment = xlLeft
.WrapText = True
.Orientation = 0
.AddIndent = False
.IndentLevel = 1
.ShrinkToFit = False
.ReadingOrder = xlContext
.MergeCells = False
End With
With Selection.Font
.Name = "Verdana"
.Size = 8
.Strikethrough = False
.Superscript = False
.Subscript = False
.OutlineFont = False
.Shadow = False
.Underline = xlUnderlineStyleNone
.ColorIndex = xlAutomatic
.TintAndShade = 0
.ThemeFont = xlThemeFontNone
End With
End Sub
"You can use the macro recording to find out the formating syntax!

Check to make sure all the cells in the data are formatted as a date and not a number.

I fixed mine by on Format Cells Go to Protection and Uncheck Locked!!!!
Presto!!!

I've had the same frustration as many of you where the formatting does not remain even though you select the "Preserve cell formatting on update" checkbox. I've found 2 things that helped me out.
- highlight more of the table and format that broader region to define the formatting for the cells that aren't maintaining the formatting you desire. Then, after refreshing, go back and change specific cells to tweak the formatting.
- Darlene's idea of conditional formatting is brilliant and works well. The only thing you'll be missing is alignment and text-wrapping.
- After doing all of this, save and close out of your file. After a moment, re-open your file and try again. I've found that, for some reason, closing the file and re-opening will allow the system to imprint these changes.

Hope this helps.

It works as soon as you untick, do all your formating and tick again.

It does work for me when I uncheck the "Autofit column widths on update".

mentira da porra isso.. nunca funcionou corretamente isso

This does not work when I try to preserve cell text alignment. For example, I want the text to be left aligned in a particular column. Upon refresh, the format resets.
Note for anyone offering to debug (if any kind soul is brave enough) - I often have multiple fields in the column section.