Apple Inc. (AAPL) is obviously best known for its iconic iPhone, but holiday demand for the iPhone X appears to be in doubt this morning. The stock traded below $170 this morning, which would result in a downgrade of Apple's weekly chart if this weakness is sustained into year end on Friday.

The stock closed last Friday at $175.01, up 51.1% year to date and in bull market territory at 52.5% above its 52-week low of $114.76 set on Jan. 3. Only two Dow stocks have outperformed Apple: The Boeing Company (BA) has a gain of 89.6% year to date, and Caterpillar Inc. (CAT) has a gain of 67.9% year to date. (See also: Apple Downgraded to 'Neutral' at Instinet.)

Here's how the numbers worked in 2017

Apple stock closed 2016 at $115.82, and my annual risky level, or price target, was $151.69. The stock reached this target on May 8. Whenever a level is exceeded during its time horizon, it becomes a pivot (or magnet), and $151.69 was crossed several times until the stock stayed above that level on Sept. 26.

At the end of June, a new semiannual risky level was calculated at $173.25 as the price target for the second half of 2017. This target was first tested on Nov. 3 as a level at which to reduce holdings in the stock. This level was last tested as a pivot (or magnet) on Dec. 20, after the stock set its all-time intraday high of $177.20 on Dec. 18.

The daily chart for Apple

Daily technical chart showing the performance of Apple Inc. (AAPL) stock
Courtesy of MetaStock Xenith

The daily chart for Apple shows that the stock has been above a "golden cross" since Sept. 6, 2016, when it closed at $107.70. A "golden cross" occurs when the 50-day simple moving average rises above the 200-day simple moving average and indicates that higher prices lie ahead. The horizontal lines show the annual pivot of $151.69 and the semiannual pivot of $173.25. Apple will likely open below $173.25 on Monday. (For more, see: What Makes Apple So Valuable?)

The weekly chart for Apple

Weekly technical chart showing the performance of Apple Inc. (AAPL) stock
Courtesy of MetaStock Xenith

The weekly chart for Apple is positive but overbought, with the stock above its five-week modified moving average of $170.31. The stock is well above its 200-week simple moving average at $118.11 and has been above this "reversion to the mean" since the week of July 1, 2016, when the average was $93.31. The 12 x 3 x 3 weekly slow stochastic reading ended last week at 83.80, up from 82.80 on Dec. 15 and above the overbought threshold of 80.00. A close on Friday below $170.31 would result in a downgrade to neutral or to negative.

Given these charts and analysis, it appears that a quarterly value level will remain at $141.84 as the level at which to buy on weakness in the first quarter, and it appears that semiannual and annual risky levels will come in around $183.60 and $191.81, respectively, as levels at which to reduce holdings on strength. (For additional reading, check out: Is Apple Planning to Use Blockchain?)