The meaning of "It's deducted from welfare agency"???

Please look at the following sentence.

I often call the Tet bonus "Tet' money" because the money which people receive cannot regarded as a bonus. It's deducted from welfare agency,which is mentioned in internal spending regulations.

* Tet -> Lunar New Year

I could understand the meaning of the words "It's deducted from welfare agency"
Does it mean that an amount of the Tet bonus an employee receives has to be deducted from a budget of the welfare agency?

And why did the writer not put an article in front of "welfare agency"?

Thank you for your answer in advance.