how much i have to show in my bank statement, wife and two kids, do i need to show myslef maintinance aswell..

plz anyone help me applying for psw visa for dependent and two kids

plz anyone help me applying for psw visa for dependent and two kids from pakistan, i m in uk more than 12 months how much i have to show in bank and what other documents are required, anyone help plz
many thanks

i need some information, if u can help me please,
i m on PSW visa now , and living in uk morethan 8 years and now i want to sponsor my wife and two kids,how much money i have to show in my account for 90 days, and what other documents required,,,
plz reply
ASAP
tnx nadeem