There are four flavors as in a reply; pick one that suits the husband best;
1. If husband is student and un-employed then NIL and for the same catena of HC’s have said so.
2. If husband is shown to be plain vanilla un-employed and is having functional two legs + two hands + two eyes + two ears + a tongue all in working conditions then Minimum Wage applicable to his State is guess work of Ld. Judge(s).
3. If husband was earlier working and has incapacitated himself then guess work of Ld. Judges(s) is based on sound probability theory of his last earning capacity.
4. If husband was working and as soon as maintenance case Notice reached him and he resigned from his job then the "resignation letter" wording should be based on “recession and or we donot want a criminal husband working for our company” then guess work of ld. Judges is based on Minimum Wage applicable in his State.
But behind all above four flavors in reference to context if the Husband first files an application for Court Commissioner appointment to check his employed / un-employed Status then he is winner as what ever a Court Commissioner states under Oath even Hon'ble SC cannot reverse the same no matter how much his Lady cries later.