Why is the annual transferred money worldwide quite different?
There is no contradiction here as not every transfer is a remittance.


  remit 
  late Middle English: from Latin remittere ‘send back, restore’


It is my understanding that the word remittance is usually used to describe transfers by foreign workers to their home countries. From Wikipedia:


  A remittance is a transfer of money by a foreign worker to an individual in his or her home country.


These transfers may be conducted via SWIFT. As such they make up a small part of all SWIFT traffic, which would also include domestic payments, international business transfers, etc. So it is quite possible that the yearly volume of remittances is $\$5 \cdot 10^{11} $ whereas the yearly volume of SWIFT transfers is $\$1.25 \cdot 10^{15} $.