Your monthly figures are correct but your math is incorrect unles you are working with NET figures. But even then you haven't considered they deduct 10% for your pension, not just the 30% which goes to the taxman.
We get 12 monthly salaries + 1 month in Jan + 1 month in July + 1 month in Dec + 1 CTS = 16 salaries per year.
Therefore:
21,976
x 16
-------
351,616
/ 2.9 (actual exchange rate 2.85 by the way but I will work with your figures)
-------
121,246 USD BEFORE TAX, GROSS, BRUTO, etc
Saludos,
OW