Use of ประจำ

[xkkpafi]

I find this word causes me constant difficulty and a struggle to truly master. For example, what additional meaning does it add to this sentence:

SEC News : สรุปแบบ 246-2 ประจำวันที่ 7 กุมภาพันธ์ 2561. Without ประจำ I guess we have "SEC News, summary (according to regulation) 246-2, 7th Feb 2561". So what does ประจำ add to this sentence? Thanks.

[Kittichai in Thailand]

Without ประจำ, the sentence essentially mean the same thing. This is added mostly because of writing formality. 

[Briggsy]

ประจำวัน = daily (a schedule that occurs every day) Or in this case every working day.

[digbeth]

if you substitute ประจำ to 'for' สำหรับ in this case, as a preposition it makes the sentence flows better, even though it is redundant and can be omitted without the loss of meaning

[xkkpafi]

Many thanks folks, I suspected that it added little extra meaning to that particular sentence.

[Sweet memory 80s]

ประจำ simply translated as "regularly" or in this specific sentence "on a regular basis (of nn days)" .

In my opinion, This sentence not even say "daily". it may means any nn days period and the latest one happen to be on this date (ประจำ-วันที่ )Feb 7, 2561  not ประจำ(วัน)-ที่ FEb 7,2561 .

Sometime this wording confuses me as well when doing the analysis but normally we use it just by memory not synthesizing the sentence so it's not the problem. 

[tgeezer]

 To parse the sentence, it can only be read one way. If the date were ประจำ then the publication would be annual. From the SEC website I think that we are supposed to see ประจำ as specific to the day. 

ข้อมูลประจำวัน data produced specific to the day.  บัตรประจำตัว card specific to the person. 

Does that work?