as if it mattered

I'm getting ready to pack up for an extended holiday break and won't be back in the office until January 2. Now that I've wrapped up all my work before I take off, I decided to do some math. I'm awful at math, but I find it is closely related to my obsession with making lists. I always calculate stuff. Distances, checking accounts, percentages. It's an obsession albeit an obsession I'm terrible at.

Anyway, I decided to calculate what my heritage is. So, here it is:
50% Italian
28% Irish
12.5% French
7% English
1.5% unknown/unverified
less than 1% German

But this didn't tell the whole story. I needed to figure out what my wife's heritage was so I could eventually calculate our daughters'.
My wife:
25% Swedish
25% Italian
12.5% Portuguese
12.5% Welsh
12.5% Irish
10.9% Unknown/unverified
1.5% English

And representing the true diversity of the United States, our daughters:
37.5% Italian
20.5% Irish
6.25% French
12.5% Swedish
4.25% English
6.25% Portuguese
6.2% Unknown
and not enough German to document

I don't know if this matters to anyone in the world, except me, but there it is. Now, go find my math errors.