3 today.  I don't track. Can't remember what I had for breakfast so no help on longer than that.  But nothing has changed...

You know bud... some of us like myself on a great day get 2 and then other people out here saying, "I get 3 every other day...".

To answer the OP, in a month I get about 6-7. I think the BEST I every did was 11 in 1 month and I've been playing for 4+ years now. Saw a YT vid where someone was saying you get 15 a month on average is either the luckiest person in the world or straight up BSing.

The 15 seems high.  Getting 2 from unm and 1 from nm like I did is very rare.   I think the average is higher than 6/7 but not 15. 

Long run average is I think about 12 based on player recorded data.

Sounds about my average luck rate. Maybe I would bump up my average to 8-9 a month. Between Sacred shards and legend books, I get both about 8-9 a month each from 4 daily chests.

I do know that my longest dry spell was 12 days though. I needed 1 more legend book to finish my skills for a champ in a CvC. Went the entire time until the start of the new CvC to get 1.

0 lol

I haven't gotten 3 Sacreds in one day in a long time, but I got 3 lego books today, which probably has the same odds as pulling 3 Sacreds.

Ive had like 20+ days dry, but the ive have like 2 weeks with at least 1 a day.  RNG gonna RNG. 

Books should have lower odds.