3.2 BILLION daily volume reported by Finnhub Stock API - this is 6446% of the float. Let’s figure this mystery out 🔎

So...

TL;DR at the top for the apes who can’t count to 10:

Finnhub.io API reported a daily volume of 3.2 BILLION for Gamestop today. Most other sources show a mere 6.2 Million. What the hell is happening?

Edit #9 (see other edits at bottom, bumped this to top because it is important) - u/barsa00 pointed out that the Finnhub data has been updated to show today’s volume as 6,196,100. I am seeing the same outcome in my code. Looks like the data has been ‘fixed’. This is as of 8:57 PM 04-06-2021. I plan to check for this abnormality in after hours tomorrow.

We’ve all likely heard of the x billion volume ‘bug’ on Think or Swim.

Glitch this, easy to explain that. Yada yada yada.

Anyways today, out of curiosity, I was playing with the Finnhub Stock API. This API allows you to use python to analyze and survey financial data from stuff as simple as current stock price to stuff like mutual fund holdings and stock split history.

My main goal in my wanderings was to compare today’s LOW volume which was ~5 million at 3:00 PM EST, to historical volume data for the past three months.

All was going well - my findings were lining up to my original inklings that today was set to be the lowest volume day in the past three months.

I set things aside for a bit, only to come back (after market close) and find that the data had changed. Like, SUBSTANTIALLY CHANGED.

Today ended as not the lowest volume day in the past three months, but instead the HIGHEST VOLUME DAY IN THE PAST THREE MONTHS.

Here are my findings:

Volume (in ascending rank) over last 90 calendar days (there were 61 trading days):

Rank	Volume	Date (MM-DD-YYYY)
1	6,129,276	01-07-2021
2	6,481,960	01-08-2021
3	7,060,665	01-12-2021
4	7,565,215	02-23-2021
5	8,175,030	02-16-2021
6	8,393,834	03-31-2021
7	9,260,795	02-17-2021
8	9,334,345	04-01-2021
9	10,042,175	03-29-2021
10	10,061,505	03-22-2021
11	11,799,914	03-18-2021
12	13,056,725	02-11-2021
13	14,034,300	04-05-2021
14	14,429,145	03-23-2021
15	14,573,264	02-12-2021
16	14,828,238	02-19-2021
17	14,927,612	01-11-2021
18	16,481,589	03-17-2021
19	17,094,924	03-30-2021
20	19,273,882	03-03-2021
21	19,476,021	02-22-2021
22	23,990,555	02-18-2021
23	24,177,877	03-24-2021
24	24,226,187	03-15-2021
25	24,677,297	03-19-2021
26	25,687,282	02-08-2021
27	25,845,899	03-12-2021
28	26,843,082	02-09-2021
29	28,312,493	03-11-2021
30	30,733,673	03-05-2021
31	32,606,893	03-04-2021
32	33,471,789	01-20-2021
33	33,783,044	03-02-2021
34	35,422,867	03-16-2021
35	36,455,036	02-10-2021
36	37,382,152	02-01-2021
37	37,430,672	03-26-2021
38	39,099,331	03-09-2021
39	42,698,511	02-03-2021
40	46,866,358	01-15-2021
41	49,793,965	03-01-2021
42	50,566,055	01-29-2021
43	50,962,337	03-25-2021
44	57,079,754	01-21-2021
45	58,815,805	01-28-2021
46	62,427,275	02-04-2021
47	63,565,620	03-08-2021
48	71,570,566	03-10-2021
49	74,721,924	01-19-2021
50	78,183,071	02-02-2021
51	81,345,013	02-05-2021
52	83,111,740	02-24-2021
53	92,194,154	02-26-2021
54	93,396,666	01-27-2021
55	93,717,410	01-14-2021
56	144,501,736	01-13-2021
57	150,308,766	02-25-2021
58	177,874,000	01-25-2021
59	178,587,974	01-26-2021
60	197,157,946	01-22-2021
61	3,223,112,896	04-06-2021

Now... we all know this isn’t true. I cross-referenced other sources which all show ~6.2M as of market close today, 04-06-2021.

So you’re probably wondering: where does Finnhub obtain their data?

Market data & corporate actions are sourced directly from the exchanges (ASX e.g), ActivFinancial, EDI and QuoteMedia. Fundamental data is sourced directly from companies' filings which we make available in SEC Filings endpoint and International Filings endpoint ETFs data is sourced from Issuers' filings and public websites.

Apes - this is absolutely madness.

To ensure I wasn’t going insane, I checked several other stocks (AMC, TSLA, AAPL). Of the others I checked, only AMC was showing this ridiculously inflated volume reported for today.

I encourage you all to participate in solving this volume mystery however you might see best fit.

For the wrinkle brained, code happy apes - play with Finnhub data to see what you can find yourself.

For the smooth brained, mom’s basement apes - ask me questions. Any other data you would like to see?

Obligatory 🚀

Edit #11 - u/HolyPhoenician did some amazing work and actually charted the data from my post.

Edit #10 - u/bosorioo found this same data anomaly. Here is their comment with the raw data and a pastebin linked to the parsed data for anyone looking for that.

Edit #9 - u/barsa00 pointed out that the data has been updated to show today’s volume as 6,196,100. I am seeing the same outcome in my code. Looks like the data has been ‘fixed’.

Edit #8 - somebody asked for the data for AMC.

Edit #7 - there were actually 61 trading days in the past 90 calendar days. My original table was missing a data point. Fixed now.

Edit #6 - in response to edit #5, the data for today shows up on some API requests but not others. Don’t want to start any conspiracies here as my sole purpose of posting was for us to analyze objective data points however the data is behaving strangely. Could be my bad code, could be craziness on the back end. This is as of 7:44 PM EST 04-06-2021.

Edit #5 - was continuing to work with the data at all - like the day just doesn’t even exist anymore - and it is no longer showing today’s data as of 7:35 PM EST 04-06-2021.

Edit #4 - improved formatting again by removing ‘(Ascending)’ note after Rank header. This makes it all look better and I note that the data is in ascending data in the text line before the table.

Edit #3 - improved formatting of the data. I know several people were wanting to play with the data themselves so hopefully this helps with that.

EDIT #2 - added commas to the volume, changed ‘v’ and ‘t’ to ‘volume’ and ‘date’; added short explainer prior to the data to ease consumption for dumb apes.

EDIT #1 - explained the ‘v’ and ‘t’ in the data. Made note to update format of the data later tonight.