SUM not working as expected in my table

Hello everybody!

I'm very new to Jaspersoft Studio and i'm facing a problem to sum values in my table. I will try to be as clear as possible.

I have an XML dataset construct like this (i've just put datas that are relevant for my question, it's not the complete XML)

<RAPPORT>
    <HEADER>[.....]
    </HEADER>
    <DONNEES>
        <RESIDENT>
            <ID>1</ID>
            <AGE>67</AGE>
            <SEXE>M</SEXE>
        </RESIDENT>
        <RESIDENT>
            <ID>1</ID>
            <AGE>77</AGE>
            <SEXE>F</SEXE>
        </RESIDENT>
        <RESIDENT>
            <ID>1</ID>
            <AGE>68</AGE>
            <SEXE>M</SEXE>
        </RESIDENT>
        <RESIDENT>
            <ID>1</ID>
            <AGE>78</AGE>
            <SEXE>F</SEXE>
        </RESIDENT>
[........]
    </DONNEES>
</RAPPORT>

So i make a table of distribution by age group like this

I have no problem to construct the table and (i think) no problem for the expression to create my variables. I use these variables to fill the table :

IF(INTEGER_VALUE($F{AGE_1} )>=85 && INTEGER_VALUE($F{AGE_1} )<=95 && $F{SEXE_1}.equals("M"),1,0)

If my age is between these values and depending the sex, i want 1 or 0. That's my expression and it's working well if i don't want to sum the result. I've 6 people (<RESIDENT>) in my XML and when i preview my table (which is in the detail area to see every change for every people when i preview). I put ascreenshot to let you see that is working this way.

We see here that the first page of the report is OK. We found a man (the "M" in orange) which is 72 years old (in red) so it put a 1 on the good cell. And all the 5 others persons in the 5 other pages of the report are OK. I always have a 1 in the good cell.

But now i want to sum all these 1 and 0 to have just one table with the sum. And that is where i have problem. I try to modify the way it's calculate so in my variable properties, i have change "nothing" to "sum" like you can see in the screen below.

But now i don't understand but i don't have the sum i need. Worst, it shows me the same even if i have only ONE person in my XML)

So we have one man of 65 years old. The value is in the good cell but why i have a 2???? It's the only person in my XML so how can i have 2 ??? Normally i should have 1 and if i have 1 other man of 60-74 years old it should be 2, and 3 if have another one , etc......

Maybe i've missed a thing to calculate this....

Hope someone can help me :)

Thanks in advance for your future answers.