Unfortunately, I don't think there is a set answer or guideline to this question, Riyadh.
There are way too many variables; some of them being: Supply of jobs, Preferences of job-seeker, Location constraints, Mobility constraints, Type of projects, and so on.
It's becoming increasingly popular to contract your services, and build a portfolio career. There's always many options for a PMP.
Depends on market condition, geography you belongs to and on industry in which you are operating in or willing to work. If market is already stagnated it may take significant time or not much luck to receive advantages from PMP.
This is like the question "How long does it take to catch a fish?". To add to Karan and Rajeev's list of variables I'd add: luck, demand vs. supply, the size of your network, seasonality...
Riyadh - Not sure I totally understand the intent of the question.
It depends. The is clearly no one size fits all answer. Sometimes a promotion/new job is waiting for someone to earn their PMP credentials.
As far as money and job type, that depends too :) What does the individual want. Obviously, no one would take a new job that does not fit their desired role/position/rewards.
Market and demand will dictate in addition to the awareness of PMP
There are many variables: conditions, market, demand, industry, experience..
If it was so clear, there would be stats.
Some say it is related to the number of CV you send, other the number of call, etc.
Many variables identified by previous comments.
How much the local market value PMP or is it value in this industry.