Update March 23:
Some basic drop rates for the last week:
Full spreadsheet here: https://docs.google.com/spreadsheets...it?usp=sharing
The method used to track mythic/M+ dungeon drop rates here is to check if a legendary is looted within 60sec after killing the last boss of a mythic dungeon. This number includes any normal mythic and M+ last boss kills, so it's just an average, but I'd guess that a good part of these are 3 chest runs. Based on this I'd say that mythic+ is still a good source for legendaries, at least if 3 chest.
Also now there has been 5 weeks since the blue post about legendary drop rate changes, so I've little more data to see how these changes have affected the KP statistics. However keep in mind that these calculations have been done with a relatively small sample size, and the KP weights used are not accurate anymore either, but I've used these same weights and similar methods as in the last calculations to make it easier to compare the numbers. So this is still just a very rough estimation:
Conclusions:
- Average KP between legendaries (after having at least 2) in the last 5 week seem to be around 600-700 KP. There may be an error margin of 100-200 KP though, depending on calculation method and the type of content used.
- The Bad Luck Protection does not seem to have much effect at all in the first 300-400 KP (or roughly 100 kills), but after that it starts to rise fast, the effect is more noticeable than in the earlier calculations.
These stats are still based on those few 1000 characters which I started tracking in october. I've also almost finished a new code that can track more characters more efficiently, but patch 7.2 is coming very soon and it looks like it will have some major changes to drop rates again, possibly making the bad luck protection much more complicated.
UPDATE Feb 22, 2017:
Here's Nighthold drop rate statistics from the last 3 weeks:
NOTES - There are several things that affect the drop rates, which makes it harder to directly compare different groups:
- People with less legendaries have higher average bad luck protection(more "killpoints"), which also increases the drop chances in these groups.
- People with more legendaries do more mythic/HC raids, which should have have higher base drop chance.
- Blizzard is regularly changing the drop chances.
- There is always some amount of statistical error.
Either way, it appears like the drop rates for people with more legendaries have increased just 1-2 week ago.
I will try to improve the tracking process and kill points calculations, maybe start to track more characters.
Full spreadsheets:
Feb 22: https://docs.google.com/spreadsheets...it?usp=sharing
Feb 15: https://docs.google.com/spreadsheets...it?usp=sharing
Feb 8: https://docs.google.com/spreadsheets...it?usp=sharing
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Blizzard confirmed on Feb 17. that each time you received a legendary, the starting chance (base chance) to get the next legendary did get lower (aka diminishing returns):
https://us.battle.net/forums/en/wow/topic/20753149009
But they also said that they changed this recently, so that NOW each legendary after the 2nd one should have the same starting chance.
Because of these changes all the statistics below are "outdated" now, in a sense that they don't represent the current drop rates, however they still show how the system worked in the past.
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Update Feb 6. 2017:
First some clarifications:
- The data we can get from armory is somewhat limited and there are a lot of variables, so the results here are a combination of real numbers and some estimated numbers. Therefore it's hard to say exactly how accurate these results are.
- These statistics have been showing some kind of diminishing returns, at least for the first 4 legendaries.
- The average effort(KP) needed for the next legendary appears to be around 40-50% more than for previous one. (it's not "twice as much", that is false/old information)
- It's still mostly random and statistics only give info about probabilities, in the end some people still get more lucky than others.
Here are new drop statistics from Nighthold bosses for the past week. This time I was able to sort the results by the number of legendaries that those chars already had, and even though the sample size could be better, it again looks like the drop chance is lower for people with more legendaries.
Full spreadsheet with more details: https://docs.google.com/spreadsheets...it?usp=sharing
I also did some new Kill Points statistics, with little more data and better tracking for Mythic+, PvP and emissary quests. Example: at 2100 KP the average legendary count is 3, however this is only average, which means you have about 20% chance to have just 2, 58% chance to have 3, 20% chance to have 4 and 1-2% chance to have something else. Please note that the Kill Points model is just a tool to estimate droprates, not scientifically accurate proof of something (see the spreadsheet and rest of this post for more detailed information).
Full spreadsheet here: https://docs.google.com/spreadsheets...it?usp=sharing (work in progress)
Extra speculation - Theoretical model for legendary drop chance:
Drop_Chance = Base_Chance * BLP / GLP
->
Drop_Chance = (0.0018 * KPevent) * MAX(1; 1+((KPcount/250)-1)*2) / (2^LegendaryCount)
Not to be taken too seriously, but when simulated it gives quite similar results as all the statistics in this thread. This formula is based on info from this thread, with numbers tweaked to fit the statistics.
---------older stuff below----------
Update Jan 4. 2017: I made one more stat spreadsheet, now for top 500 EU characters sorted by AP, to see that the legendaries are still dropping quite regularly also for people who have farmed mythics more than anyone else.
This time I pulled more detailed armory data to have better tracking for mythic+ and other things. However with this data I can't track bad luck protection in same way as before, also I have no way to see how many legendaries these characters already have, but I'd guess most of them have 4 or more. So this data can't be directly compared to earlier KP statistics as is, also using just the averages does not necessarily show the "true" drop rates on such unlinear system influanced by BLP, but it gives at least some idea about how often they drop.
Full spreadsheet with more details here: https://docs.google.com/spreadsheets...it?usp=sharing
UPDATE Dec 15 - Latest stat spreadsheet now for the 10th week, and more analysis on how much already looted legendaries and bad luck protection affects the drop rate.
1. Drop rate vs how many legendaries looted
In the Nov 24. update I showed the average KP needed for next legendary which doubled after each legendary, but it didn't take into account the future effect from bad luck protection, and therefore it only showed the average of current situation, but not the real expected average. Also using just the average does not tell the whole truth. Anyway here's the new averages from total 10 weeks of data:
edit: Just to clarify: the "avg KP needed" in this chart is NOT useful for predicting the true avg, because it doesn't count in BLP, so the avg numbers are misleading(too high), but I leave it here for reference purposes: http://i.imgur.com/BklpMEy.gif
To explain the KP system a little: each time I find certain activity from feed data, that can be raid boss kill, weekly chest loot, or mythic+ epics, I increase the KP counter for that character. There is also alot of untrackable activities like emissary quests, HC dung's, pvp chests, world boss etc and to balance those I give 2 KP daily to everyone, but keep in mind that these are all high ilvl characters, so they get majority of legendaries from raids and mythic+. All these weights are based on average drop rates (see chart at bottom) but it obviously isn't very accurate for those untrackable activities or for mythic+. But for now it gives a Rough estimation.
BUT as said, this average KP above isn't very good for predicting exact drop rates, which are dynamic due to BLP. Also there isn't enough data to see what happens to drop rate after 4th legendary, except that it seem to be higher now, 5 chars confirmed to have 5th, while 3 weeks ago there was none.
Anyway the following chart may be more informative:
Here it shows that to have 50% chance for a drop, you'd need 210KP for 1st, 430KP for 2nd, 590 KP for 3rd and maybe around 1000KP for 4th legendary (total 2230 KP). So maybe it's not as bad as needing a double effort to get the next one, but it still shows noticable dimishing returns. Also of course it's still possible that someone gets very lucky and gets 4 legendaries with first 400 KP, while 6% haven't got even 1st yet.
-> Full data Google Spreadsheet here - Includes also a sheet where you can examine results for only certain subgroups (need to copy spreadsheet to edit it).
But... analysing these kind of dynamic drop rates is a bit complicated and would need further verifications, there are still few big issues that may cause inaccuracies:
1. Perhaps the biggest problem is that the activity feed doesn't give data for all activities and isn't always 100% accurate. Even if I'd save the data daily, it doesn't always show all the loot. Could this cause noticable bias in results? I'm not sure, but I might need a more accurate data source to improve the results.
2. Is the sample size enough big and the formulas good enough? Also the KP values are just estimated, especially for mythic+.
3. This is just pure speculation: but different activities might increase the BLP differently. Maybe only mythic+ has dimishing returns? Maybe there's weekly limit for BLP?
4. Blizzard can change the algorithms any time, and already did couple times during the collection of this data. Soon all these numbers may be irrelevant.
So I wouldn't take all these numbers as cold hard facts, but they should provide a better estimation of the drop system than pure quessing or a small group of people.
2. Bad luck protection
Here is a chart that shows drop rate for 10 KP (equals roughly 2-3 raid boss kills or mythic+'s), in relation to how many KP collected since last legendary, and how many legendaries looted before. The effect of BLP is quite noticable. (full spreadsheet in link above)
3. General legendary drop rate statistics
The drop rates for mythic+ at the end are still estimations, due to limited data, but it should show a rough idea what the real %'s are.
-> Full data Google Spreadsheet here
Extra: List of 159 legendary items with ID, name, and how many times each has dropped in last 4 weeks + source of drop
Old links:
Nov 24 BLP/KP spreadsheet here
Week 7 spreadsheet here
Week 4 spreadsheet here
Week 3 spreadsheet here
Week 2 spreadsheet here
Week 1 spreadsheet here
Stats for the last 24h (Oct 27) compared to previous weeks reset days, to see if 7.1 had influence to drop rates
Method used:
1. I saved the names of top 10k characters of Draenor-EU from wowprogress.com, sorted by ilvl.
2. Fetched item and activity feed from Blizzard API for all these chars few times per week.
3. Used PHP code to parse interesting parts of loot data, insert it into spreadsheet and calculate some %'s.