A teacher netted 1800 Euros after of 4 months at a private school ( Sept. 2009 - Dec. 2009), in Barcelona, Spain. ( a new job)
For the month of January 2010, the new tax year, she has netted 1500 Euros and told by the school that the tax is now based on annual deduction and not on the four months.
Cannot understand why there should be a difference. Can this be correct?

Maria:

This sounds like a homework problem, which are NOT answered on this forum as a matter of policy.

Further, this forum deals exclusively with U.S. taxes.

Both are valid reasons no one answered your post.