How Many Stocks in the ADD

[joker]

How Many Stocks are in the ADD? The advance decline ratio seems like it is a valuable tool, does anyone know the exact number of stocks in the ADD?

$ADD = x number of stocks

[PlaceboTrader]

See if you can find a straight answer on this one, good luck. It's well over 2000 but I think it is a variable number and I can't find any info on how often the $ADD is updated.