Technically both of those numbers are higher though, since, for example, Michishige is ~22.85 Tanaka is ~22.5, etc. That is to say, unless ~today~ is their birthday, all of the girls are older than their solid "age" number, which would result in an overall higher average.
EDIT: Ah, looks as though as I was posting, Menno make have taken the months bit into account. Hooray!
I used the days, that's the most easy way to do it in Excel.
days since birth/365.25
The .25 is for leap year correction. You could do it even more precise, when you only count the days after the last birthday and divide that through 366 (or 365 if is not a leap year), but the outcome will not be that much different.
I'll admit that I find myself going "Yeah~ Yeah~ Yeah~ Yeah~ Pyoko Pyoko Jump!" HOWEVER this is three, four months AFTER the song came out. And I only know the song because I'm a MM fan. MM can't really afford another Pyoko Pyoko, plus the hardcore fans spoke with their wallets; sucky sales for a sucky single.
One Two Three can honestly go in any directions, it's such a generic title. The Matenrou Show seems a little gimmicky but I guess we'll see.