I think it's really hard to put a percentage on it though! If there is an obvious imbalance then OK, but otherwise it's difficult to say and I would definitely rate some tasks as "counting" for more than others.
I do most of the cooking, but that's because I am quicker at it and I enjoy it. But if I weren't able, DP is perfectly capable of heating things up cooking for us, and will do.
I do more of the cleaning - dusting, hoovering, whatever. I'd say we're about equal on the washing up. He does more of the laundry.
I sort most of the bills and things, but that's because DP often works away during the week and isn't on the spot in order to deal with phoning to correct the incorrect council tax bill that's just arrived though. However, if I told him "X needs to be done, here are the details, I haven't got time to do it" then he would do it while away.
In terms of DIY he does almost everything because I am useless at it. With DD at the moment I do slightly more but I think that will even out as she gets older.
I've never even thought about whether this is 50/50 or what, but I don't think that either of us feel hard done by and that's what's important surely? Of course I could try harder will DIY and he could try to cook a bit more. But then I would have to eat his food.