@Sachin
income will be after tax, after your loan EMI (if taken when ur wife resided wid you) and after deducting all other liabilities (expenses related to dependent parents/siblings if any)..
Check old posts i also post the case law.Right now i cant find in my pc but it is available in lci forum.Now i got .
Here is your link:https://www.lawyersclubindia.com/mobile/forum/message_display_mobile.asp?group_id=26665
Generally,the judge should consider following factors;It depend upon husband earning(income),lifestyle,his or her a status in a society ,dependancy,a standard of living ,other expenditure etc.
Now what has been said by Supreme Court,
The Supreme Court, while commenting on the elusive nature of fixation of amounts of maintenance, had stated as follows, in
Jasbir Kaur Sehgal (Smt) v. DistrictJudge, Dehradun and Ors (1997) 7 SCC 7;
"No set formula can be laid for fixing the amount of maintenance. It has, in the very nature of things, to depend on the facts and circumstances of each case. Some scope for leverage can, however, be always there. The court has to consider the status of the parties, their respective needs, the capacity of the husband to pay having regard to his reasonable expenses for his own maintenance and of those he is obliged under the law and statutory but involuntary payments or deductions. The amount of maintenance fixed for the wife should be such as she can live in reasonable comfort considering her status and the mode of life she was used to when she lived with her husband and also that she does not feel handicapped in the prosecution of her case. At the same time, the amount so fixed cannot be excessive or extortionate."
The present position of law (maint.), from its bare reading is evident that the following principles emerge from the judgments till date:-
A. Maintenance depends upon the summation of all the facts of the situation [as laid down in Re.: Dr. Kulbhushan Kunwar Vs. Raj Kumari AIR 1971 SC 234].
B. For granting maintenance, the scale and mode of living, the age, habits, wants and class of the life of the parties has to be regarded [as laid down in Re.: Dr. Kulbhushan Kunwar Vs. Raj Kumari AIR 1971 SC 23].
C. Maintenance being such that the wife could live in a reasonable comfort; considering her status and mode of life which she was used to while living with her husband [as laid down in Re.: Jasbir Kaur Sehgal Vs. District Judge, Dehradun and Ors. 1997 (7) SCC 7]
D. During the pendency of the suit for maintenance, which may take a considerable time to attain finality, the wife cannot be forced to face starvation till she is subsequently granted maintenance from the date of the filing of the suit [as laid down in Re.: Neelam Malhotra Vs. Rajinder Malhotra and Ors. AIR 1994 Delhi 234 ].
E. Maintenance must necessarily encompass a provision for residence. Maintnenace is given so that the lady can live in the manner, more or less, to which she was accustomed. [as laid down in Re.: Komalam Amma Vs. Kumara Pillai Raghavan Pillai and Ors. SLP (C) No. 3670/2005 decided on 14th November, 2008]
F. Maintenance, necessarily must encompass a provision for residence. Maintenance is given so that the lady can live in the manner, more or less, to which she was accustomed. The concept of maintenance must, therefore, include provision for food and clothing and the like and take into account the basic need of a roof over the head. [as laid down in Re.: Mangat Mal Vs. Punni Devi (1995) 6 SCC 88]
G. Maintenance must vary according to the position and status of a person. It does not only mean food and entertaiment. [as laid down in Re. : Maharani Kesarkunverba v. I.T. Commissioner, AIR 1960 SC 1343]
All authorities quoted detailed text readers may find in www.indiankanoon.org