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Transcripts for the above video clip:
Pivot Tables 2007- Calculated Fields;
Calculated Items
Excel gives you the
ability to actually create your own formulas within the Pivot Table.
There are two ways to do this - something called calculated fields
and another called calculated Items.
Just to explain the
difference between fields and items, because it is very important,
you need to look at the underlying data. In the underlying data a
field is defined as a column in this case, so for example the bill
is a field, internet cost is a field, charged to MTN is a field. So
if we are going to do a calculated field – what we are asking is
to do some sort of calculation in two fields – for example we
are going to work out what the net profit is
and all we are going to do is take the bill, subtract the
charge, subtract other costs to get an answer. This compared to
calculated items – here let’s say we have got days of the week,
Wednesday, Thursday, Friday etc. We may want to actually add up
items within a field – so for example
I want all the Saturdays and the
Sundays to be added up to create a weekend. So the difference
between the two is that in calculated fields there are distinct
columns that we are doing something to. In calculated items we are
actually working within the field and adding, subtracting or some
sort of calculation to the items in the field.
Focusing on the
Calculated Field first.
Here we have a Pivot Table – there are dates, we have got
the total bill, the costs for the charge and some other costs. We
would like to know what the net profit is. In order to do a
calculated field, click anywhere within the Pivot Table. You have
the Pivot Table ribbon, you’ll
see there is something called Formulas- when I click on it you’ll
see there is something called Calculated Fields. And there is the
Calculated Items. At the moment it is greyed out but again we are
focusing on Calculated Fields. When I click Calculated Fields the
following appears and it asks – give this field a name – I am
going to call it Net Profit for example and then you just have to
create the formula and the Row Labels or the fields are shown here
so we know that the formula is going to be – you want it to take
the bill and either click insert field or double click and when I
say, in this case, add
the charge (because it is a negative number) add the other
costs. I am happy with that. I could say Add and do another one. But
for now I’m going to say OK. You’ll see what it has done,
it has created a new column and if we look at our fields
you’ll see there is another item called Net Profit. Now in the
underlying data base we already had a Net Profit calculation. I have
just shown you how to do it in a calculated field.
If you want you can do some quick checks – you’ll see
those add up to .09, .09 and if we actually pull through the proper
net profit field, we format it,
you’ll see it gives you the same number.
So that is the way to create a calculated field. The benefit
of a calculated field is if I now go and I am going to do some sort
of a grouping here – the months is OK, the calculated field will
continue to do the calculation based on the information it has. I am
just going to ungroup this.
Now let’s look at
a calculated item. I
have created another Pivot table. We have taken the day of the week
which is a field, we have put it into the Row labels- we can see
that the one represents a Monday, Tuesday, Wednesday etc and we have
got the sum of a bill. What we would like to do is to
add up the Saturday and a Sunday to tell us what we do on a weekend.
I know that logically it should come to 267 by adding those up. In
order to do a calculated item, what we need to do is click in the
field where the item exists. So
if I click here in a Pivot Table and I try do a calculated item
you’ll see it is greyed out. You need to click in the field in
which the item exists. When I go here you’ll see now you can see
something called Calculated Item. When I click on it a very similar
dialogue box appears to Calculated Formulas. I will just give it a
name – I will call it “Weekend Total”. You’ll see the field
is already identified as day of the week – all you need to do is
now give it a formula – we get it out of the items. So by clicking
on the day of the week it has identified
all the unique items. We are going to say please add up all
the Saturdays and the Sundays. Before I press OK, just notice this
– because this is one of the problems with calculated items. We
have already said that that must be about
267 or so. Notice
that the grand total is 2237 – when I click OK we now have a new
item in the field and it comes to the 267 which is correct, you’ll
see it adds it up. But you have to be very careful because what
you’ll notice is this new total has been included (double counted)
in the
items which means it has
affected the grand total- the grand total is now 2505. So this
number is now added in, in which case it means there is some double
counting. If you do need to use this, you probably need to get rid
of these grand totals and the way you do it is right click on a
Pivot Table, go to the Pivot Tables Options and work through some of
these items to remove it.
To Edit or to remove
the calculated field or item- again you click in the field and go to
Calculated Items. To find one that has already been built, click on
the drop down box, you’ll find it, click on it, you have got the
formula if you need to change it. Or if you want to delete it, click
delete, say OK and you will see you will be back to the original
Pivot Table.
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