Understanding Split-Adjusted Historical Stock Prices

Summary

The document examines how a stock split appears in historical price data, using Apple’s seven-for-one split in June 2014 as its example. It contrasts a reported pre-split closing price near $645 with a finance site’s historical table showing a price around $92 for the same date, and asks why the larger figure is absent from the chart. The author distinguishes regular closing prices from adjusted closing prices and notes that the displayed adjusted values are lower still.

The post is a data interpretation question rather than an explanation or answer. It illustrates that historical price displays may present split-normalized values even when users expect unadjusted closes, while adjusted close can also account for other corporate actions. No source reconciliation or data-provider methodology is supplied, so the example does not resolve which field or display convention produced the figures. Readers should verify a vendor’s adjustment policy before comparing historical levels across a split.

Key ideas

• Stock splits change the share count and the nominal price per share.
• Historical charts may show prices restated to account for a split.
• Adjusted close can incorporate corporate actions beyond a split.
• The document raises a vendor data interpretation issue but does not resolve it.
• Data adjustment conventions should be checked before comparing prices across a split.

Tags

# Stock spilt not reflected in historical data


# Stock spilt not reflected in historical data












According to this article, Apple's stock split 7:1 on June 9, 2014. The stock supposedly closed at around \$645 on June 6 and was supposed to open at around \$92 on June 9. I confirmed that a split took place on June 9 through Yahoo Finance; however, according to the historical data table shown there, the closing price on June 6 was \$92.22 and the closing price on June 9 was \$93.70. (These are the regular closing prices, not adjusted. The adjusted closing prices are \$84.85 and \$86.21 for June 6 and June 9, respectively.) My understanding was that the regular closing prices are not adjusted for splits while adjusted closing prices are. If this is true, why is the \$645 closing price not shown in the chart on Yahoo Finance on the days leading up to the split?

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