I have twelve events every day from 8am to 8pm every hour.

I have two columns in Excel spreadsheet: “date and time” and “description”.

I need to add date and time stams for each cell of “date and time” column in the format

```
16/11/2011 08:00
```

So the first twelve cells will look like that:

```
16/11/2011 08:00
16/11/2011 09:00
16/11/2011 10:00
16/11/2011 11:00
16/11/2011 12:00
16/11/2011 13:00
16/11/2011 14:00
16/11/2011 15:00
16/11/2011 16:00
16/11/2011 17:00
16/11/2011 18:00
16/11/2011 19:00
16/11/2011 20:00
```

Then the next day shall come:

```
17/11/2011 08:00
17/11/2011 09:00
17/11/2011 10:00
17/11/2011 11:00
17/11/2011 12:00
17/11/2011 13:00
17/11/2011 14:00
17/11/2011 15:00
17/11/2011 16:00
17/11/2011 17:00
17/11/2011 18:00
17/11/2011 19:00
17/11/2011 20:00
```

Is there a way I can get the column filled in automatically for several months?

Put your first date in cell `A1`

:

```
16/11/2011 08:00
```

And in cells `A2`

and below, add the formula:

```
=A1+TIME(IF(HOUR(A1)=20,12,1),0,0)
```

and then drag down your formula till where you need.

[EDIT] Explaining a little bit the formula: in order to keep the formula quite simple, it is rather specific.Meaningly,

- the formula starts at the previous date
`A1 +`

- then, it adds some hours (with the
`TIME`

function) but no minutes nor seconds (`0,0)`

i.e. see the end of the formula - to choose the number of hours to add, it checks wether the previous date hour is
`8pm`

(i.e.`HOUR(A1) = 20`

).- If so, it adds
`12`

hours so that the new date is at`8am`

the next morning. - If not, it adds only
`1`

hour (next event)

- If so, it adds

`WEEKDAY=6`

) and hour is `8pm`

(`HOUR(A1)=20`

). If so, it adds two days (just add `2`

because date in Excel are stored as serial number and unit is a day). ```
=A1+TIME(IF(HOUR(A1)=20,12,1),0,0) + IF(AND(HOUR(A1)=20,WEEKDAY(A1)=6),2,0)
```

Tags: date, excelexcel, time