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//
//  Formula Name:    Coppock Curve
//  Author/Uploader: Tomasz Janeczko 
//  E-mail:          tj@amibroker.com
//  Date/Time Added: 2001-06-16 08:17:23
//  Origin:          Originally developed by Edwin Sedgwick Coppock
//  Keywords:        moving average
//  Level:           basic
//  Flags:           indicator
//  Formula URL:     http://www.amibroker.com/library/formula.php?id=9
//  Details URL:     http://www.amibroker.com/library/detail.php?id=9
//
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//
//  The Coppock Curve was developed by Edwin Sedgwick Coppock in 1962.
//
//  It was featured in the November 94 issue of Technical Analysis of Stocks
//  & Commodities, in the article "The Coppock Curve", written by Elliot
//  Middleton.:
//
//  Taken from Stocks & Commodities, V. 12:11 (459-462): The Coppock Curve
//  by Elliott Middleton
//
//  "We are creatures of habit. We judge the world relative to what we have
//  experienced.
//
//  If we're shopping for a mortgage and rates have been in the teens (as they
//  were in the early 1980s) and then drop to 10%, we are elated.
//
//  If, however, they've been at 8% and then rise to 10%, we are disappointed.
//  It all depends on your perspective.
//
//  The principle of adaptation-level applies to how we judge our income
//  levels, stock prices and virtually every other variable in our lives.
//  Psychologically, relativity prevails..
//
//  SIMPLEST FORMS
//
//  The moving average is the simplest form of adaptation-level. Moving average
//  crossover rules accurately signal the onset of periods of returns outside
//  the norm, whether
//
//  positive or negative. This makes moving average crossovers useful to
//  traders who want to get a boost on entering or exiting stocks or funds.
//
//  The oscillator is also based on adaptation-level, although in a slightly
//  different way. Oscillators generally begin by calculating a percentage
//  change of current price from
//
//  some previous price, where the previous price is the adaptation-level or
//  reference point. The mind is attuned to percentage changes because they
//  represent returns. If you
//
//  bought Microsoft Corp. stock (MSFT) at $50 and it goes to $80, you make 60%
//  before dividends.
//
//  If you bought Berkshire Hathaway (BRK) at $4,000 and it rises to $4,030,
//  the same dollar gain, you make 0.75% before dividends.
//
//  It's the percentage change that counts. Relativity again.
//
//  Coppock reasoned that the market's emotional state could be determined by
//  adding up the percentage changes over the recent past to get a sense of the
//  market's
//
//  momentum (and oscillators are generally momentum indicators ). So if we
//  compare prices relative to a year ago - which happens to be the most common
//  interval - and we
//
//  see that this month the market is up 15% over a year ago, last month it was
//  up 12.5% over a year ago, and 10%, 7.5% and 5%, respectively, the months
//  before that, then
//
//  we may judge that the market is gaining momentum and, like a trader
//  watching for the upward crossover of the moving average, we may jump into
//  the market."
//
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/*
Coppock Curve

AFL Implementation by Tomasz Janeczko
*/

Graph0 = EMA( ROC( MA( C, 22 ), 250 ), 150 ) / 100;