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Select Custom for Display in Column Properties dialog or Format Cell dialog. Choose ##+## or #+##M from Custom Display combo.
| Custom Display | Description |
|---|---|
| *nn | *nn is to specify the number of significant digits |
| .nn | .nn is to specify the number of decimal places |
| S | Scientific |
| E | Engineering |
| ##+## | 123 will be displayed as 01+23 |
| #+##M | 123 will be displayed as 1+23M |
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