I see a lot of differences between the adjusted close price in the Yahoo finance web interface and the adjusted close price returned from their API.

Take Apple (AAPL) as an example. If you look up the the adjusted close on October 31, 2016 (and many other dates) you will see these differences.

If I look up the historical quote via the web interface then I see an adjusted close price of 113.54. However, if I look up that same quote via their API, then I get the adjusted close price as 112.96.

What's happening here?

By the way, I also checked Apple's adjusted close price data on the split date (6/9/2014) and the adjusted close reported on web interface was an accurate reflection of the split ratio, but the API data was not. Does that mean I cannot trust the API data?

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    The web interface isn't showing an adjustment for dividends, even on the maximum time line. The close price equals the adjusted close price until the split. The web interface doesn't seem to be accounting for dividends in the adjusted price while the api table does. If you're building something out of this, I'd suggest you spend some time understanding what adjustment is is being applied and how it's actually taking place. – quid Feb 4 '17 at 18:11
  • @quid thanks for the reply. I noticed that the ui wasn't accounting for dividends, but I would expect that to only impact the adjusted price on the dividend payment date. Am I incorrect in that regard? – The Gilbert Arenas Dagger Feb 4 '17 at 18:24
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    A dividend payment should change every adjusted close price that precedes it. From the web interface you can download the displayed data and the adjusted close price is listed correctly, the prices before 11/2/16 will be adjusted for the dividend. – quid Feb 4 '17 at 20:11
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    @quid thank you. If you want to post your commentary as an answer, I will accept it. Your explanation bridges the gap between the web interface and the api while highlighting the differences... exactly what I was looking for. – The Gilbert Arenas Dagger Feb 4 '17 at 20:23