Advance-Decline Line
A running total of the number of advancing securities minus the number of declining securities each period.
Formula
A/D Line = Previous Value + (Number of Advancing Securities - Number of Declining Securities)
Unit
ratio (x, times)
In depth
The line counts securities equally regardless of size, which is exactly the point: a capitalisation-weighted index can rise on a handful of large companies while most listed securities fall, and the advance-decline line makes that visible. In India, where index moves are frequently driven by a small number of heavyweights, the divergence between the index and this line is a recurring observation. Its absolute level is arbitrary and depends on when the count began, so only direction and divergence carry content. The measure describes participation and predicts nothing.
Worked example
The index gains 0.8% while 1,240 securities decline against 680 advancing. The A/D line falls by 560 on a day the index rose — the gain came from a few large constituents, not from the market as a whole.
Illustrative figures, chosen so the arithmetic is easy to follow. Not a live price and not a valuation of any company.
Educational reference only
This entry explains what “Advance-Decline Line” means. It is not investment advice and not a recommendation to buy or sell any security. Any numbers above are illustrative, not live prices, and nothing here predicts price direction or rates a stock. Consider your own circumstances and consult a SEBI-registered investment adviser before acting.