Here are comments and chart form the latter stages of 2021.

Each bar is derived from one week of trading activity.
After week 50, markets got a sideways bar for the 3. time. Stay awake! A break either direction could quickly show way for important further developments. Low 15650, and high 16460.
After week 49, markets see an inside bar showing sideways direction on a weekly scale. Tuesday and Wednsday's FOMC meeting could esily trigger further direction and breakout up or down.
After week 48, there is weakness to the latest weekly bar signalled by the lower low (15.538) and the lower high (16.456).
After week 47, blue bars are still in control. There is a higher low and a higher high, and a renewed All-Time-High (16.768).
After week 46, the weekly chart gives a new all-time-high and another perfect bar with a higher high and higher low.
After week 45, there is an equal high (16.450) as to week 44 and a higher low. There is more strength than weakness for the weekly perspective. Nasdaq100 in currently hoovering around its all time high levels.
After week 43, the index clearly makes a higher low and a higher high. Downside to watch are ticks below 15.050.
After week 42, a higher high and a higher low is created in the weekly chart. 14.998 is not to be challenged in week 43 in order to hold on to the weekly strength.
After week 41, lower highs continues for the Nasdaq100 index, but there is now also a higher low. Last week was an inside week. The next break could be explosive, but you never know if an inside week leads to weakness or strength.
After week 40, lower lows and lower highs. The index must trade above 15.300 in order to gain traction towards September highs.
After week 39, the index is making a lower low at 14.540 signalling lower prices to come. In order to see markets return its earlier positive momentum on a weekly time scale, Nasdaq100 will have to challenge 15.400.
After week 38, markets sees a lower low and a lower high. It looks like the index has topped out for now. In order to keep bars in colour Red, 15.350 is not to be exceeded - and stay there.
After week 37, 15.230 is the low point. There is a lower high (weak sign) and uptrend is still intact.
After week 36, 15.084 is the low point. The weekly uptrend is still intact.
After week 35, 14.910 is the low point of the week, and the number to challenge if prices starts to decrease.
After week 34, the low point for this latest bar is 196 points above week 33.