顺势指标衡量了价格与移动平均线的相对位置。它可以用来显示市场的超买超卖区域或者是对趋势减弱发出信号。该指标理念与布林带类似，但它是通过指标线而不是超买超卖水平表现出来。

顺势指标是由Donald Lambert创造的，并在他的Commodities Channel Index: Tools for Trading Cyclic Trends 一书中有所描述。

交易信号

顺势指标最好和追踪止损结合起来使用。

市场处于盘整期

• 如果CCI从下向上穿过-100，做多。
• 如果CCI自上而下穿过100，做空。

趋势市场

背离是不多见的、很强的交易信号。它们多被用于中线交易。
• 看涨背离做多。
• 看跌背离做空。
 
示例：

IBM 公司股价与  14 日CCI ，根据交易信号进场，并在第二天设置跟踪止损买入、卖出的挂单。

S1: 做空—顺势指标从超买区域下降。该笔交易在趋势反弹的S2处止损。
S2: 做空—看跌背离。该笔交易在S3处的反弹止损。
S3: 做空—三重看跌背离。
L1: 做多—顺势指标从超卖区域上升。第二日收盘价低于该日，单子被扫损。2日后，追踪止损的挂单成交。
S4: 做空—顺势指标从超买区域下降。
L2: 做多—顺势指标从超卖区域上升。
S5: 做空—顺势指标从超买区域下降，出现看跌背离。
L3: 做多—顺势指标从超卖区域上升，出现看涨背离。
?: 市场正处于趋势中：价格超过前期高点。价格从超买区域下降时不要做多——等待看跌背离。
S6: 做空—看跌背离。
S7: 更强烈的交易信号—三重看跌背离。

设置

顺势指标的默认设置是20日周期，超买超卖水平为100/-100.

顺势指标的计算公式

顺势指标的计算公式十分的复杂。下面是20日CCI 的计算公式：
1. 计算中值:TP：

          (高点 + 低点 + 收盘价) / 3
2. TPMA：中值的20日平均值。
3. TP值减去TPMA
4. CCI计算方法：
• 过去20日内的TP值各自减去今日的TPMA值。
• 计算出20个结果的和，并除以20.
• 计算结果除以 0.015.

其他的时间周期（比如10日或30日）可以直接替代20日。

 
Commodity Channel Index
The Commodity Channel Index measures the position of price in relation to its moving average. This can be used to highlight when the market is overbought/oversold or to signal when a trend is weakening. The indicator is similar in concept to Bollinger Bands but is presented as an indicator line rather than as overbought/oversold levels.
The Commodity Channel Index was developed by Donald Lambert and is outlined in his book Commodities Channel Index: Tools for Trading Cyclic Trends.
Trading Signals
Commodity Channel Index is best used in conjunction with trailing buy- and sell-stops.
Ranging Market
• Go long if the CCI turns up from below -100.
• Go short if the CCI turns down from above 100.
Trending Market
Divergences are stronger signals that occur less frequently. They are mostly used to trade intermediatecycles.
• Go long on a bullish divergence.
• Go short on a bearish divergence.
 
EXAMPLE
IBM Corporation with   14 day Commodity Channel Index. The days shown are the signal days. Trades are entered using trailing buy- and sell-stops on the day following.
S1: Go short - Commodity Channel Index turns down above the overbought line. This trade is stopped out at the rally before S2.
S2: Go short - bearish divergence. This trade is stopped out during the rally before S3.
S3: Go short - bearish triple divergence.
L1: Go long - Commodity Channel Index turns up from below the oversold line. The next day closes below the low of the signal day, causing the trade to be stopped out. A trailing buy-stop would stop us back in two days later.
S4: Go short - Commodity Channel Index turns down above the overbought line.
L2: Go long - Commodity Channel Index turns up from below the oversold line.
S5: Go short - Commodity Channel Index turns down above the overbought line and bearish divergence occurs.
L3: Go long - Commodity Channel Index turns up from below the oversold line and bullish divergence occurs.
?: The market is now trending (evidenced by the break above the previous high).
Do not go short when Commodity Channel Index turns down above the overbought line - wait for a bearish divergence.
S6: Go short - bearish divergence.
S7: Even stronger signal - bearish triple divergence.
Setup
The default Commodity Channel Index is set at 20 days with Overbought/Oversold levels at 100/-100. To alter the default settings - Edit Indicator Settings.
See Indicator Panel for directions on how to set up an indicator.
Commodity Channel Index Formula
The Commodity Channel Index calculation is fairly complicated. Here is the formula for 20-day CCI:
1. Calculate Typical Price ("TP"):

          (High + Low + Close) / 3
2. Calculate TPMA: a 20-day simple MA of TP.
3. Subtract TPMA from TP
4. Divide the result by the following:
• Subtract today's TPMA from TP for each of the last 20 days.
• Sum the absolute values and divide by 20.
• Multiply the result by 0.015.
Any other time period (e.g. 10 days or 30 days) can be substituted for 20.

本文翻译由兄弟财经提供

文章来源：http://www.incrediblecharts.com/indicators/commodity_channel_index.php