How people set their Salary Expectations ?

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How do people set their Salary expectations?
Particularly the one who are returning to job-market after a
break, returning from other country or switching careers.
For instance when I returned from Japan, and was looking forward to my
career shift, I asked. Many were tight-lipped.
Even friends won’t share the details. And you will find them very diplomatic
like “it depends”.
So when one more colleague is planning to return from Japan
and mentioned he is expecting a salary of 20 Laks per annum as Project
Manager in  IT firm.
I just explored casually (not some serious research though) …
One friend, who is senior architect in one of the leading
software firm, & based in Pune mentioned a thumb rule at his work-place. 

We normally stick
with 1.5 times experience. If he has 10 years of experience, reasonable
expectation is 14 to 15 Laks per annum. And further this is moderated by
skill-set, technology, certifications, kind of organizations, projects that one
worked with and need of resource at that point of time.

Just couple of days back, I was talking to another friend. She was with consulting firm, and then resigned for some continuing education (not
really increasing her marketability in corporate world). She mentioned that she is expecting a salary
of 18 Laks per annum. I was little surprised and asked source of this figure.  Her argument…

Typically MBA receives the average salary around 7
Laks per annum. She has around 14 years of post-MBA experience.  So she added one Laks per year of experience
and discounted for the two years of break.

Both the responses forced me to think.
Though there are salary surveys, ( here too ), user-forums, and reports on
compensation trends, they don’t really answer such special cases. 
More-over, these answers clearly underlined the entitlement
philosophy
of compensation, so for every year worked ,pay-raises are kind of expected.

Any thoughts or comments ? 

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