This 'DAR CARD' information is from one of Nicholas Darvas' out-of-print books in which he said he was still able to pick breakouts in 74/75.

HOW TO DRAW A DAR-CARD

1. When the price of a rapidly rising stock reaches a resistance point which it does not surpass for 3 or more consecutive days, that point represents the top of the box.
2. If, after falling from the upper limit, the stock reaches a downward resistance point which it does not penetrate for 3 or more consecutive days, that level represents the bottom of the box.
3. The shaded danger level is indicated when the price falls 5% below the bottom of the box.

HOW I USE THE DAR-CARD

1. A stock is in a rising trend when it is in its topmost box. As long as it remains there its price fluctuations should be ignored and the stock is a HOLD.
2. If the price of the stock moves above the top of this topmost box, the stock becomes a BUY. A 10% stop-loss should be set on the first breakout.
3. Having formed a new higher box, if the price falls below the bottom into the shaded area of this box the stock is a SELL.
4. There is no reason to HOLD or BUY a stock that is not in its topmost box.

   Also

5. Darvas buys only stocks making new 52 week highs
6. He now does not buy new breakouts, only the '2nd' breakout to a new high.