Today's Downturn?

[kdf]

Downturns are good because people drop out of mining and just go to speculating.  Thus the miners see a decrease in difficulty.

[netrin]

put a 21 period simple moving average on a bitcoin chart

Why 21 exactly?

[FXTrader]

21 gives a good feel for the direction of the intermediate trend.  Anything from 15 to 30 is a good period for medium term.  If you have a more short-term perspective use the 10 and for a more long-term perspective use the 50.

The most widely watched moving average numbers are 20, 50, and 200 so you will see in more active markets that "gamers" push price around these numbers and prices are very responsive to them.

I learned the specific number 21 from a very successful proprietary currency day-trader.

[Cosbycoin]

any idea when its gonna hit 15$ again? waiting for payout....

Might be a while before then.