From:
https://nxtforum.org/index.php?topic=4788.msg91304#msg91304###
Asset ID
3267494002243225342
Ticker symbol
ShortBTCD
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This a synthetic shorting product for the price of BitcoinDark (BTCD). If the Bitcoin-denominated price of BTCD (BTCD/BTC) goes down, ShortBTCD goes up (and vice versa). Initial Price: 100 NXT.
ShortBTCD aims to generate a daily percentage gain inverse to that of BTCD/BTC. Issuer will support ShortBTCD Target Price with orders on the Asset Exchange.
ShortBTCD Target Price equals the most recent ShortBTCD Daily Reference Price minus the percentage change in BTCD/BTC from the most recent BTCD Daily Reference Price. ShortBTCD Daily Reference Price is set daily at or around 10 am ET to current ShortBTCD Target Price. BTCD Daily Reference Price is a weighted average as reported at coinmarketcap.com or comparable substitute, at issuer's discretion, at or around 10 am ET. Issuer will maintain price support on a best effort basis and makes no assurances of timeliness or accurate calculation or reporting of involved prices.
Daily reference price updates and history will also be enshrined at twitter.com/shortnxt.
Also worth noting, given the extreme volatility in BTCD, the orders maintained by the issuer on the order book will tend to be smaller than the actual available liquidity at/near the fair market value. Given the occasional slow block, it's unwise to maintain an enormous bid or ask that can quickly become a foolish price to be picked off. So if you're looking to enter/exit a larger position than the order book seems to accommodate, just leave the rest of your order on the book and - assuming the price is still appropriate - it will be filled (up to the point that the issuer's actual risk limits are reached).
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For those of you that are not quite understanding all this, this allows you to lock in the current price. of course it it keeps going up, you are losing money on the shortBTCD, but its canceled out by the gains. If you match the value of shortBTCD with the value of your BTCD, then your combined value for both should stay pretty much the same.
So, you can keep staking while locking in a nice ATH price and if it does drop, then you lose money on the BTCD, but make up for it with the shortBTCD. Then you sell the shortBTCD right before the price goes back up.
Now, shortBTCD is not a realtime instrument, it is daily, so it is more for hedging your overall risk without needed to actually sell any BTCD
this is not for everyone, but if you understand it, it is quite useful in situations, especially if we ever get back to thinly traded markets where even one BTC would move the price
James