If you want to add decimal points in Excel cells automatically, here is how you can do that. Although you can use the in-built options to enable this setting, you can also use the Registry Editor ...

All the cells of negative numbers will become red, while the positive numbers will remain the same. You can create your own custom format in Excel to highlight negative numbers. Select the range ...

For example, to add the numbers 10, 20, and 30, click the desired cell, then type the formula below and hit Enter. =10+20+30 The result (60) will appear in the selected cell.