Like the above poster mentioned, hard to say without specifics.
If you have boys, I'd honestly expect a major reduction in groceries. When my brother and I (I'm a woman) left, I think my parents had their bill cut in half, maybe even a bit more because they always ordered an extra pizza on pizza night and got extra food if we ordered take out.
Misc. expenses: what are these? What do you buy your kids? Toilet paper and toiletries? Clothes and shoes?
Utilities: not a huge reduction, unless your kids are home 24/7 or doing utility-heavy things (multiple showers, tv on all day).
Insurances: obviously a big expense and huge savings once that's no longer on you.