Hi there
iv'e never sat down and done the maths myself.
Here are some things to consider that might help;
purchase of a cot/basinette, high chair, pram
diapers - around 30 a week as a basic guide
formula if you are not breastfeeding - I used a tin a week (maybe a little more)
sterilizing equipment / tablets etc.
Clothing - babies grow incredibly quickly and you are always buying clothes
childcare - if you intend to go to work, you may have to pay for childcare
on top of that you have to consider cost for rent, food, petrol to and from work etc.
Best wishes, sandy